Brake Caliper options
11-12-2016, 07:47 PM
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Brake Caliper options
I have a stock 84 Firebird and decided I want better brakes. I've already gotten new pads and slotted rotors, now I just need some calipers to go with them. Right now I'm looking at the PowerStop S4071's (if I stay OE spec) Wilwood 140-12097R's, Summit Racing SUM-BK181R's, and the Speedway Motors(?) (Big Bore Metric) 91031040's. If anyone has any experience with any of these calipers or knowledge of them, please chime in.
Another question I have is if I upgrade my front setup but leave my rear setup stock (newly rebuilt drums) will that hurt the brake bias? If so how badly? Thanks in advance
Another question I have is if I upgrade my front setup but leave my rear setup stock (newly rebuilt drums) will that hurt the brake bias? If so how badly? Thanks in advance
11-12-2016, 10:51 PM
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Re: Brake Caliper options
I wouldn't waste your money on those. Your basically paying $400 for otherwise stock calipers. Aluminum so you will shave some weight, and they look a little better but still TINY.
Brake retrofits are so cheap these days you can probably do a an LS conversion for that, and a C5 conversion for a few bucks more.
I just did a fully custom CTS-V setup for well under 1k.
Brake retrofits are so cheap these days you can probably do a an LS conversion for that, and a C5 conversion for a few bucks more.
I just did a fully custom CTS-V setup for well under 1k.
11-16-2016, 07:53 AM
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Re: Brake Caliper options
Any of the stock replacement calipers at rockauto.com are the cheapest you will find anywhere and are of good quality.
Don't be fooled by the single piston design of the stock front calipers. Even though they are a single piston, its piston area is larger than almost all performance calipers including the CTS-V. A larger piston area caliper will give better clamping force than a smaller piston area caliper regardless of how many pistons you have.
Thought the CTS-V caliper piston area is smaller, it benefits come from being a fixed (instead of floating) caliper and is more than likely has less caliper flex. The CTS-V biggest advantage is its larger diameter rotor which provides better leverage to stop the car over a smaller diameter rotor.
If working with the stock front brake setup and the stock size front rotor your options are limited to caliper and pad choices.
If you can lock up your front brakes with the stock system, you have adequate brakes and not enough tire.
If you want to improve your stock front brake system braking power, you will need to install a caliper with a larger piston area. The ONLY calipers I know of that will do this is a caliper with a single 2.75" piston. Wildwood is the only one I have verified with a 2.75" piston as some of the other advertised 2.75" big bore calipers have less than 2.75". The other advantage of the Wilwood 2.75" piston caliper is that it is a little lighter than stock, but it maintains the same or or has better rigidity because of its design. There is a difference between this caliper housing and a stock housing if you compare them side by side.
There is no performance advantage to aluminum other than it being lighter. Steel is better at reducing caliper flex than aluminum and any of the aftermarket aluminum replacement calipers that will bolt in will likely have more caliper flex. The aluminum versions will not have any performance advantage over a stock replacement cast iron version regardless of the piston count or piston size.
The next thing that will help with braking is pads. This is fairly subjective and you will need to do you research on which pad is best for you.
The other things that will help with braking are replacing the older rubber lines with new rubber lines or aftermarket stainless steel braided flexible brake lines. Old rubber brake lines will start to balloon with age reducing braking performance.
Don't be fooled by the single piston design of the stock front calipers. Even though they are a single piston, its piston area is larger than almost all performance calipers including the CTS-V. A larger piston area caliper will give better clamping force than a smaller piston area caliper regardless of how many pistons you have.
Thought the CTS-V caliper piston area is smaller, it benefits come from being a fixed (instead of floating) caliper and is more than likely has less caliper flex. The CTS-V biggest advantage is its larger diameter rotor which provides better leverage to stop the car over a smaller diameter rotor.
If working with the stock front brake setup and the stock size front rotor your options are limited to caliper and pad choices.
If you can lock up your front brakes with the stock system, you have adequate brakes and not enough tire.
If you want to improve your stock front brake system braking power, you will need to install a caliper with a larger piston area. The ONLY calipers I know of that will do this is a caliper with a single 2.75" piston. Wildwood is the only one I have verified with a 2.75" piston as some of the other advertised 2.75" big bore calipers have less than 2.75". The other advantage of the Wilwood 2.75" piston caliper is that it is a little lighter than stock, but it maintains the same or or has better rigidity because of its design. There is a difference between this caliper housing and a stock housing if you compare them side by side.
There is no performance advantage to aluminum other than it being lighter. Steel is better at reducing caliper flex than aluminum and any of the aftermarket aluminum replacement calipers that will bolt in will likely have more caliper flex. The aluminum versions will not have any performance advantage over a stock replacement cast iron version regardless of the piston count or piston size.
The next thing that will help with braking is pads. This is fairly subjective and you will need to do you research on which pad is best for you.
The other things that will help with braking are replacing the older rubber lines with new rubber lines or aftermarket stainless steel braided flexible brake lines. Old rubber brake lines will start to balloon with age reducing braking performance.
Last edited by manualbrakes.com; 11-16-2016 at 09:41 AM.
11-16-2016, 09:28 AM
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Re: Brake Caliper options
Autozone has factory front calipers for $15
11-16-2016, 10:13 AM
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Re: Brake Caliper options
Malibudave.
The piston area on the stock caliper is 4.4 sq.in. while piston area on the CTSV calipers is 4.3 sq.in. not much of a difference. This nets you similar brake clamping force on a larger rotor. The larger rotor gives you a higher brake torque. This should also alow a more optimal pedal feel.
The size of the pad any affects fade characteristics and pad wear.
If your so worried about clamping force get a smaller master and reduce piston size.
Now a calipers effectiveness is also measured by the caliper stiffness which is why larger 4 and 6 piston fixed calipers are able to have smaller net piston area. Their fixed or static nature allows them to realize increased clamping force.
There are more benefits to running a fixed 4 pot to a stock single sliding. Ease of changing pads, more static, more even pad wear. Larger rotor will also disipate heat better, and minimize fade. Better pedal modulation. The CTSV calipers also alow you to keep the same brake bias.
No one is saying the stock setup doesn't stop the car. But the fact is it is sub pat for anything other than daily driving. The caliper and rotor is very very small.
As far as pads, semi metalic stop better than ceramic or blends. Period. At the expense of possibly more noise and more metal dust and caliper wear. Subjective would be the brand you choose.
The piston area on the stock caliper is 4.4 sq.in. while piston area on the CTSV calipers is 4.3 sq.in. not much of a difference. This nets you similar brake clamping force on a larger rotor. The larger rotor gives you a higher brake torque. This should also alow a more optimal pedal feel.
The size of the pad any affects fade characteristics and pad wear.
If your so worried about clamping force get a smaller master and reduce piston size.
Now a calipers effectiveness is also measured by the caliper stiffness which is why larger 4 and 6 piston fixed calipers are able to have smaller net piston area. Their fixed or static nature allows them to realize increased clamping force.
There are more benefits to running a fixed 4 pot to a stock single sliding. Ease of changing pads, more static, more even pad wear. Larger rotor will also disipate heat better, and minimize fade. Better pedal modulation. The CTSV calipers also alow you to keep the same brake bias.
No one is saying the stock setup doesn't stop the car. But the fact is it is sub pat for anything other than daily driving. The caliper and rotor is very very small.
As far as pads, semi metalic stop better than ceramic or blends. Period. At the expense of possibly more noise and more metal dust and caliper wear. Subjective would be the brand you choose.
Last edited by blackbmagic; 11-16-2016 at 10:24 AM.
11-16-2016, 11:53 AM
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Re: Brake Caliper options
Malibudave.
The piston area on the stock caliper is 4.4 sq.in. while piston area on the CTSV calipers is 4.3 sq.in. not much of a difference. This nets you similar brake clamping force on a larger rotor. The larger rotor gives you a higher brake torque. This should also alow a more optimal pedal feel.
The size of the pad any affects fade characteristics and pad wear.
If your so worried about clamping force get a smaller master and reduce piston size.
Now a calipers effectiveness is also measured by the caliper stiffness which is why larger 4 and 6 piston fixed calipers are able to have smaller net piston area. Their fixed or static nature allows them to realize increased clamping force.
Larger rotor will also disipate heat better, and minimize fade.
No one is saying the stock setup doesn't stop the car. But the fact is it is sub pat for anything other than daily driving. The caliper and rotor is very very small.
As far as pads, semi metalic stop better than ceramic or blends. Period. At the expense of possibly more noise and more metal dust and caliper wear. Subjective would be the brand you choose.
The piston area on the stock caliper is 4.4 sq.in. while piston area on the CTSV calipers is 4.3 sq.in. not much of a difference. This nets you similar brake clamping force on a larger rotor. The larger rotor gives you a higher brake torque. This should also alow a more optimal pedal feel.
The size of the pad any affects fade characteristics and pad wear.
If your so worried about clamping force get a smaller master and reduce piston size.
Now a calipers effectiveness is also measured by the caliper stiffness which is why larger 4 and 6 piston fixed calipers are able to have smaller net piston area. Their fixed or static nature allows them to realize increased clamping force.
Larger rotor will also disipate heat better, and minimize fade.
No one is saying the stock setup doesn't stop the car. But the fact is it is sub pat for anything other than daily driving. The caliper and rotor is very very small.
As far as pads, semi metalic stop better than ceramic or blends. Period. At the expense of possibly more noise and more metal dust and caliper wear. Subjective would be the brand you choose.
I will agree to going to a larger rotor is the best and is more costly. Going to a smaller master cylinder is not always an option when using stock components. The stock third gen master cylinder already has a small pressure bore of 24mm. There are no smaller bore master cylinders that bolt up in the stock location for a third gen F-body. For power brakes, 24mm bore master cylinder is really good for pressure. Also since the stock third gen master cylinder is a step bore master cylinder, it can provide the volume needed for the larger Wilwood 2.75" piston caliper. If using stock front brakes, the 2.75" bore caliper is the third best upgrade after a good set of pads and a good set sticky tires.
If you can lock up the tires, you brakes are adequate. If you have brake fade, you pads are not adequate and you will need a more aggressive pad that needs more heat.
In the original post, he already has the rotors and pads. The next upgrade would be getting rebuilt calipers from your local auto parts store, rockauto.com brands, AFCO new stock replacement calipers (part number 6635003 and 6635004), or installing larger calipers (like Wilwood part number 120-8936).
A larger piston caliper is the best upgrade for a stock brake setup if you already have chosen the pads and tires.
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11-16-2016, 12:34 PM
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Re: Brake Caliper options
I'll agree with that. Having not taken apart the stock calipers can one assume that the 4 pot brembos also have a larger base diameter?
The bias remains reletively constant when swapping to the brembos from stock.
Also, what I was trying to avoid was the OP buying a $400 set of willwood single piston calipers when you can do a full brake upgrade for just slightly more. By going LS1, C5 or 4 pot CTSV/brembo. I could have done my CTSV for $750 or less had I gone with parts store pads, rubber hoses and blank rotors.
Of course this doesn't include the wheels you would need since these won't fit behind stock wheels. My setup is custom for 17" wheels, normally you need 18"s for the brembos.
The bias remains reletively constant when swapping to the brembos from stock.
Also, what I was trying to avoid was the OP buying a $400 set of willwood single piston calipers when you can do a full brake upgrade for just slightly more. By going LS1, C5 or 4 pot CTSV/brembo. I could have done my CTSV for $750 or less had I gone with parts store pads, rubber hoses and blank rotors.
Of course this doesn't include the wheels you would need since these won't fit behind stock wheels. My setup is custom for 17" wheels, normally you need 18"s for the brembos.
Last edited by blackbmagic; 11-16-2016 at 12:37 PM.
11-16-2016, 02:31 PM
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Re: Brake Caliper options
Right now I'm looking at the PowerStop S4071's (if I stay OE spec) Wilwood 140-12097R's, Summit Racing SUM-BK181R's, and the Speedway Motors(?) (Big Bore Metric) 91031040's. If anyone has any experience with any of these calipers or knowledge of them, please chime in.
AFCO have NEW (not rebuilt or reman) stock replacement calipers. Part numbers are 663-5003 and 6635004. No deposit.
Since the fronts do most of the braking, I think your bias will be OK.
Last edited by manualbrakes.com; 11-16-2016 at 06:12 PM.
11-16-2016, 08:26 PM
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Re: Brake Caliper options
Actually that is not true - and I will tell you why.
Braking is the application of deceleration through a system of parts, including the tires, wheels, wheel studs, rotors, calipers, brake lines, and finally pressure through the brake lines - which is the driver pressing down on the pedal.
Here is the part you are getting confused with - the distance it takes to stop a car traveling at 60mph for instance. Stock 3rd gen with 10.5" brakes and a great summer tire in 245-50-16 is going to use 130 to 140' to stop when cold - and it will fade after the 2nd stop very badly. Replace the stock front brakes with a basic 13" 2 piston kit (Baer, LS1, C4HD) and you just dropped into the 105' range on the same exact tires. And it is a lot harder to lock up a 13" kit than it is a stock 10.5" brake system. You won't drop anything with stock brakes if you move up to a wider and/or stickier tire - they just don't have the friction to improve.
Now if you are talking modern over-braked cars with sophisticated ABS systems (a Ferrari 488 with 15.7" front brakes), every single one of those cars doesn't have enough tire.
Braking is the application of deceleration through a system of parts, including the tires, wheels, wheel studs, rotors, calipers, brake lines, and finally pressure through the brake lines - which is the driver pressing down on the pedal.
Here is the part you are getting confused with - the distance it takes to stop a car traveling at 60mph for instance. Stock 3rd gen with 10.5" brakes and a great summer tire in 245-50-16 is going to use 130 to 140' to stop when cold - and it will fade after the 2nd stop very badly. Replace the stock front brakes with a basic 13" 2 piston kit (Baer, LS1, C4HD) and you just dropped into the 105' range on the same exact tires. And it is a lot harder to lock up a 13" kit than it is a stock 10.5" brake system. You won't drop anything with stock brakes if you move up to a wider and/or stickier tire - they just don't have the friction to improve.
Now if you are talking modern over-braked cars with sophisticated ABS systems (a Ferrari 488 with 15.7" front brakes), every single one of those cars doesn't have enough tire.
11-16-2016, 11:02 PM
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Re: Brake Caliper options
Here is the part you are getting confused with - the distance it takes to stop a car traveling at 60mph for instance. Stock 3rd gen with 10.5" brakes and a great summer tire in 245-50-16 is going to use 130 to 140' to stop when cold - and it will fade after the 2nd stop very badly. Replace the stock front brakes with a basic 13" 2 piston kit (Baer, LS1, C4HD) and you just dropped into the 105' range on the same exact tires. And it is a lot harder to lock up a 13" kit than it is a stock 10.5" brake system. You won't drop anything with stock brakes if you move up to a wider and/or stickier tire - they just don't have the friction to improve.
I will argue that you will get the same stopping distance with any brake system if either system can put the tires at the limit of locking them up. The only reason the distance will be longer, if on the first stop, the tires could not be locked up because of inadequate brakes, brake fade occurred during the first 60 to zero stop (which is plausible), or the brakes could not be modulated efficiently at the point of lockup. A larger rotor should lock up easier because it has better leverage if all other things are equal, but it should also be easier to modulate the braking better with the brake pedal. This may also contribute to shorter stopping distances. It should be easier to lock up your tires with a larger rotor with less effort by the driver, if not, why would you need to upgrade other than to absorb the heat better.
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Stock front brake systems can be made to work well. Yes the 10.5" rotor is smaller and cannot absorb the heat if the brakes are pushed to the limits. But if your car is a daily driver, when are you pushing it to its limits? For the stock front brake system, the improvements will come from stickier tires, brake pads, then upsizing the calipers with 2.75" (versus the stock 2.5") diameter pistons.
For the stock brake system, you should
1st choose the tires for your needs.
2nd choose the pads for your needs.
3rd upsize the caliper to one with a larger diameter piston if needed.
Daily driver needs street pads. Drag race car will most likely be OK with street pads as they only are braking hard once. A daily driver that is a weekend autocross car will need to change out their pads for that event to take the heat. These autocross pads will get better and better with more and more heat.
11-17-2016, 07:44 AM
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Re: Brake Caliper options
You can't modulate a 10.5" rotored single iron piston brake system as you can with a 13" 4 piston (or even 2 piston) system. You are applying a lot of pinch on the rotor from one side on a very small area. I'm not capable of explaining it, but maybe someone else can.
Many modern cars indeed do have much larger brakes for heat concerns - but on sub 4K lb vehicles, a 14" or even 13" with a 2pc rotor and a 4 piston caliper is more than adequate to outrun the tires for braking friction. Of course if you buy a $300k car (like the 488), you want the best brakes and larger wheels and tires to be modern looking. The 488 with all that hardware is barely able to match a good 3rd gen system in 60 to 0 braking due to the tiny front tires they use as it is a mid engined vehicle. Simple physics.
Many modern cars indeed do have much larger brakes for heat concerns - but on sub 4K lb vehicles, a 14" or even 13" with a 2pc rotor and a 4 piston caliper is more than adequate to outrun the tires for braking friction. Of course if you buy a $300k car (like the 488), you want the best brakes and larger wheels and tires to be modern looking. The 488 with all that hardware is barely able to match a good 3rd gen system in 60 to 0 braking due to the tiny front tires they use as it is a mid engined vehicle. Simple physics.
I will argue that you will get the same stopping distance with any brake system if either system can put the tires at the limit of locking them up. The only reason the distance will be longer, if on the first stop, the tires could not be locked up because of inadequate brakes, brake fade occurred during the first 60 to zero stop (which is plausible), or the brakes could not be modulated efficiently at the point of lockup. A larger rotor should lock up easier because it has better leverage if all other things are equal, but it should also be easier to modulate the braking better with the brake pedal. This may also contribute to shorter stopping distances. It should be easier to lock up your tires with a larger rotor with less effort by the driver, if not, why would you need to upgrade other than to absorb the heat better.
These cars are over braked to absorb the heat when the car is pushed to its braking limits.
These cars are over braked to absorb the heat when the car is pushed to its braking limits.
11-17-2016, 11:15 AM
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Re: Brake Caliper options
Yes, Paul definitely knows his stuff about wheels, brakes, and tech info
I had a 10.5" disc setup in the car and swapped over to a 13" C4HD setup
I also had a stock drum brake setup and swapped over to a 12" C4HD setup
While I don't have any data or actual 60-0 distances I can tell you that this is a HUUUUGE improvement over the stock brake setup. I will probably never need to upgrade the brake setup for this car because it does so well.
I had a 10.5" disc setup in the car and swapped over to a 13" C4HD setup
I also had a stock drum brake setup and swapped over to a 12" C4HD setup
While I don't have any data or actual 60-0 distances I can tell you that this is a HUUUUGE improvement over the stock brake setup. I will probably never need to upgrade the brake setup for this car because it does so well.
11-17-2016, 02:53 PM
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Re: Brake Caliper options
You can't modulate a 10.5" rotored single iron piston brake system as you can with a 13" 4 piston (or even 2 piston) system. You are applying a lot of pinch on the rotor from one side on a very small area. I'm not capable of explaining it, but maybe someone else can.
Many modern cars indeed do have much larger brakes for heat concerns - but on sub 4K lb vehicles, a 14" or even 13" with a 2pc rotor and a 4 piston caliper is more than adequate to outrun the tires for braking friction. Of course if you buy a $300k car (like the 488), you want the best brakes and larger wheels and tires to be modern looking. The 488 with all that hardware is barely able to match a good 3rd gen system in 60 to 0 braking due to the tiny front tires they use as it is a mid engined vehicle. Simple physics.
Many modern cars indeed do have much larger brakes for heat concerns - but on sub 4K lb vehicles, a 14" or even 13" with a 2pc rotor and a 4 piston caliper is more than adequate to outrun the tires for braking friction. Of course if you buy a $300k car (like the 488), you want the best brakes and larger wheels and tires to be modern looking. The 488 with all that hardware is barely able to match a good 3rd gen system in 60 to 0 braking due to the tiny front tires they use as it is a mid engined vehicle. Simple physics.
Clamping force is clamping force, no matter how its applied to the rotors. Spread out along the rotor or in one area of the rotor it does not matter. How it affects the brake pad is when it will matter.
All things being equal, lower piston area, less clamping force.
I got my numbers below from post #140 from this link.
http://www.pro-touring.com/threads/1...of-KORE3/page7
All things being equal, lets look at the numbers.
Pedal ratio: 6 to 1
Pressure Applied: 100 ft-lb
Pad Co Efficient of Friction: .45
Tire Diameter: 25.5"
Master Cylinder Size: 7/8" (.0875")
Master Cylinder Area: .601 sq-in
Line Pressure: 998 psi
Inputs:
C4 HD Rotor: 13"
C4 HD Caliper Piston Diameters: 1.5 x 2
Piston Area: 3.534 sq-in
Clamping Pressure: 3527 lbs
Rotor Torque: 860 ft-lb
Tire Force: 809
Inputs:
F-body rotor: 10.5"
F-body Caliper Piston Diameter: 2.5"
Piston Area: 4.909 sq-in
Clamping Pressure: 4899 lbs
Rotor Torque: 964 ft-lb
Tire Force: 907 lb
Rotor Torque is better in the stock F-body brake set up.
Add a 2.75" bore caliper, with a larger bore master cylinder:
Master Cylinder Size: 24mm (.0945")
Master Cylinder Area: .701 sq-in
Line Pressure: 856 psi
F-body rotor: 10.5"
Wilwood Big Bore Caliper Piston Diameter: 2.75"
Piston Area: 5.94 sq-in
Clamping Pressure: 5985 lbs
Rotor Torque: 1001 ft-lb
Tire Force: 942 lb
Caliper Flex does play a small roll and so does fixed and floating designs, but it is something you will not notice on the street.
Rebuild you stock system with quality 2.5" calipers, new brake lines, reman master cylinder, add wider stickier tires and you will have great braking performance.
If you are locking up your tires, your tires are the limitation to your braking, not your brakes. If you are pushing your car to brake fad, then you will need to change the brake pads out to a more aggressive pad to handle the heat.
11-17-2016, 07:27 PM
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Re: Brake Caliper options
Dave,
Unfortunately that is not how brakes work in reality. If it were all about piston area, you would just get a more powerful booster and larger piston in your calipers and we would all be stopping at the limit of adhesion...
But a single 2.75" piston clamping down on 1 side of a rotor is not going to be as optimal as a 4 piston caliper with the same surface area clamping down on both side of the rotor over a much larger area. I'm no expert, but the point of where the pad contacts the rotor gets very hot - sometimes enough to make the rotor glow red or even yellow - I would think the more you spread that heat out - the better the braking.
There is no way a single piston 10.5" OEM brake system even with the best pads, rotors, and other parts is going to out stop a 13" kit on the same tires. I am talking a 25 to 40ft difference in 60 to 0 braking that will increase as the stock system fades after the first stop.
Unfortunately that is not how brakes work in reality. If it were all about piston area, you would just get a more powerful booster and larger piston in your calipers and we would all be stopping at the limit of adhesion...
But a single 2.75" piston clamping down on 1 side of a rotor is not going to be as optimal as a 4 piston caliper with the same surface area clamping down on both side of the rotor over a much larger area. I'm no expert, but the point of where the pad contacts the rotor gets very hot - sometimes enough to make the rotor glow red or even yellow - I would think the more you spread that heat out - the better the braking.
There is no way a single piston 10.5" OEM brake system even with the best pads, rotors, and other parts is going to out stop a 13" kit on the same tires. I am talking a 25 to 40ft difference in 60 to 0 braking that will increase as the stock system fades after the first stop.
A single piston floater caliper clamps (pinches) on both sides of the rotor. You don't double the clamping force by have 4 pistons with two on both sides of the rotor, that is not how the math works out. The calculation for piston area is the area of all 4 pistons (2 on each side of the rotor) added together divided by 2. If you have a twin piston floater caliper with the pistons are one one side of the rotor, the piston area is piston area of each piston is added together. if you have a single piston caliper, its the piston area of one caliper.
Clamping force is clamping force, no matter how its applied to the rotors. Spread out along the rotor or in one area of the rotor it does not matter. How it affects the brake pad is when it will matter.
All things being equal, lower piston area, less clamping force.
I got my numbers below from post #140 from this link.
http://www.pro-touring.com/threads/1...of-KORE3/page7
All things being equal, lets look at the numbers.
Pedal ratio: 6 to 1
Pressure Applied: 100 ft-lb
Pad Co Efficient of Friction: .45
Tire Diameter: 25.5"
Master Cylinder Size: 7/8" (.0875")
Master Cylinder Area: .601 sq-in
Line Pressure: 998 psi
Inputs:
C4 HD Rotor: 13"
C4 HD Caliper Piston Diameters: 1.5 x 2
Piston Area: 3.534 sq-in
Clamping Pressure: 3527 lbs
Rotor Torque: 860 ft-lb
Tire Force: 809
Inputs:
F-body rotor: 10.5"
F-body Caliper Piston Diameter: 2.5"
Piston Area: 4.909 sq-in
Clamping Pressure: 4899 lbs
Rotor Torque: 964 ft-lb
Tire Force: 907 lb
Rotor Torque is better in the stock F-body brake set up.
Add a 2.75" bore caliper, with a larger bore master cylinder:
Master Cylinder Size: 24mm (.0945")
Master Cylinder Area: .701 sq-in
Line Pressure: 856 psi
F-body rotor: 10.5"
Wilwood Big Bore Caliper Piston Diameter: 2.75"
Piston Area: 5.94 sq-in
Clamping Pressure: 5985 lbs
Rotor Torque: 1001 ft-lb
Tire Force: 942 lb
Caliper Flex does play a small roll and so does fixed and floating designs, but it is something you will not notice on the street.
Rebuild you stock system with quality 2.5" calipers, new brake lines, reman master cylinder, add wider stickier tires and you will have great braking performance.
If you are locking up your tires, your tires are the limitation to your braking, not your brakes. If you are pushing your car to brake fad, then you will need to change the brake pads out to a more aggressive pad to handle the heat.
Clamping force is clamping force, no matter how its applied to the rotors. Spread out along the rotor or in one area of the rotor it does not matter. How it affects the brake pad is when it will matter.
All things being equal, lower piston area, less clamping force.
I got my numbers below from post #140 from this link.
http://www.pro-touring.com/threads/1...of-KORE3/page7
All things being equal, lets look at the numbers.
Pedal ratio: 6 to 1
Pressure Applied: 100 ft-lb
Pad Co Efficient of Friction: .45
Tire Diameter: 25.5"
Master Cylinder Size: 7/8" (.0875")
Master Cylinder Area: .601 sq-in
Line Pressure: 998 psi
Inputs:
C4 HD Rotor: 13"
C4 HD Caliper Piston Diameters: 1.5 x 2
Piston Area: 3.534 sq-in
Clamping Pressure: 3527 lbs
Rotor Torque: 860 ft-lb
Tire Force: 809
Inputs:
F-body rotor: 10.5"
F-body Caliper Piston Diameter: 2.5"
Piston Area: 4.909 sq-in
Clamping Pressure: 4899 lbs
Rotor Torque: 964 ft-lb
Tire Force: 907 lb
Rotor Torque is better in the stock F-body brake set up.
Add a 2.75" bore caliper, with a larger bore master cylinder:
Master Cylinder Size: 24mm (.0945")
Master Cylinder Area: .701 sq-in
Line Pressure: 856 psi
F-body rotor: 10.5"
Wilwood Big Bore Caliper Piston Diameter: 2.75"
Piston Area: 5.94 sq-in
Clamping Pressure: 5985 lbs
Rotor Torque: 1001 ft-lb
Tire Force: 942 lb
Caliper Flex does play a small roll and so does fixed and floating designs, but it is something you will not notice on the street.
Rebuild you stock system with quality 2.5" calipers, new brake lines, reman master cylinder, add wider stickier tires and you will have great braking performance.
If you are locking up your tires, your tires are the limitation to your braking, not your brakes. If you are pushing your car to brake fad, then you will need to change the brake pads out to a more aggressive pad to handle the heat.
11-17-2016, 08:38 PM
#17
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Re: Brake Caliper options
I think the main issue here is your looking at clamping pressure as the be all end all of brake performance. Like Paul said if that was the case everyone would go with a large single piston caliper, and a smaller piston in the master.
What you want is a well balanced system..hard, soft, long, short..better pedal modulation, heat dissipation/cooling (swept area), and leverage.
Using a larger rotor while keeping the piston area the same, gives you unobstructed brake efficiency. Adding brake torque at NO expense. Something you just cant do with just increasing the piston size, or decreasing master size. Increasing the caliper piston/or decreasing the master piston size gives you a longer and softer pedal which many associate with cheesy brakes.
Forget about locking up brakes. Any system can basically lock up. You want to be able to stop the car without locking up the brakes, but not have to use the biggest baddest stickiest tire to band-aid locking up.
One step further, using a fixed caliper has a few advantages over a slider. Sliding the caliper can use up to 100psi of pressure just to move the caliper. Sliding pins/bolts can become stuck, bent, etc and require maintenance. Changing pads is a pain, but an upgrade over drums.
The only moving parts of a fixed caliper are the pistons, again reducing pedal travel. They dont flex like a sliding caliper, decreasing pedal travel and firming the pedal. A big plus is they are super easy to change pads on as discussed earlier. Great for DD and track. Probably the biggest plus for most people is they just look great.
This is being beat to death, and has been beat to death in the past. The biggest thing you have to get over here is the assumption that more piston area = better.
Take a look at this chart. The tiny 10.5" rotors and stock calipers have no where near the most torque but have basically the largest surface area. The more I look at it the happier I get with how efficient the Gen 1 CTS-V's are that I just installed.
What you want is a well balanced system..hard, soft, long, short..better pedal modulation, heat dissipation/cooling (swept area), and leverage.
Using a larger rotor while keeping the piston area the same, gives you unobstructed brake efficiency. Adding brake torque at NO expense. Something you just cant do with just increasing the piston size, or decreasing master size. Increasing the caliper piston/or decreasing the master piston size gives you a longer and softer pedal which many associate with cheesy brakes.
Forget about locking up brakes. Any system can basically lock up. You want to be able to stop the car without locking up the brakes, but not have to use the biggest baddest stickiest tire to band-aid locking up.
One step further, using a fixed caliper has a few advantages over a slider. Sliding the caliper can use up to 100psi of pressure just to move the caliper. Sliding pins/bolts can become stuck, bent, etc and require maintenance. Changing pads is a pain, but an upgrade over drums.
The only moving parts of a fixed caliper are the pistons, again reducing pedal travel. They dont flex like a sliding caliper, decreasing pedal travel and firming the pedal. A big plus is they are super easy to change pads on as discussed earlier. Great for DD and track. Probably the biggest plus for most people is they just look great.
This is being beat to death, and has been beat to death in the past. The biggest thing you have to get over here is the assumption that more piston area = better.
Take a look at this chart. The tiny 10.5" rotors and stock calipers have no where near the most torque but have basically the largest surface area. The more I look at it the happier I get with how efficient the Gen 1 CTS-V's are that I just installed.
Last edited by blackbmagic; 11-17-2016 at 08:50 PM.
11-18-2016, 11:33 AM
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Re: Brake Caliper options
OK, I didn't think this would escalate like this. I apologize. I did not and do no intend to bash big brake conversion and I hope I didn't come across that way. Yes, a 10.5" rotor is one of the smallest especially on a performance car. Yes, a 10.5" rotor will heat soak easier and induce fade easier.
If we go back to the original post, they are looking for calipers. Best option for a stock system is a bigger bore caliper, but the limitation to most braking systems is aways going to be the tires first. A stock caliper will do the job effectively on a stock system with pads that are for what the driver needs. If the original poster wants big brake system, then there are many options to choose from.
If you go up on rotor size, you go up in weight, if using production type rotors. Is it possible that this weight increase could actually decrease braking performance? Yes, it is possible.
If you put a caliper that had a larger piston area on CTS-V or C4 HD brakes, with all other things about the caliper being equal, braking will improve because you will have better clamping force.
IF you put a caliper that had a larger piston area on any brake system, with all other things about the caliper being equal, your stopping will be better.
Brake fade can be overcome with the correct pad selection. Brake fade on a daily driver will be NON existant in most situations when drivng normally. 60 to 0 brake testing is a test for fade. I agree that a larger rotor will dissipate the heat better reducing brake fade until the larger rotor is saturated with heat also. On a daily driver, brake fade is not an issue unless you are pushing the brakes to its limits which is hard to do on the street. If it is a track car, you will want to change out the pads to a more aggressive pad to handle the heat. If the CTS-V or C4 HD pads that are good on the street are used on the track, you will have brake fade if you are pushing the braking limits.
More piston area is better, all other things about the caliper being equal.
Larger diameter rotor is better than a 10.5" rotor because you have better leverage.
Choose the pad for the driving situation. Street pads for daily driving. Track pads for the track.
Choose the best tire for your driving situation. Street car may want a 400-500 UTQG for long lasting wear. Track car may want to go with a 0-200 UTQG. The lower UTQG number will brake better on a dry track.
If we go back to the original post, they are looking for calipers. Best option for a stock system is a bigger bore caliper, but the limitation to most braking systems is aways going to be the tires first. A stock caliper will do the job effectively on a stock system with pads that are for what the driver needs. If the original poster wants big brake system, then there are many options to choose from.
- ANY brake system will have better stopping distances with stickier tires, all other things being equal. That is a fact.
- Going to a larger rotor increases leverage to stop the car better with the same piston area. That is a fact.
- Going to a larger rotor will reduce fade until the rotor is saturated with heat and the pad is not designed for the heat. Fact
- Going to a caliper with a larger piston area for more clamping force will improve braking performance regardless of rotor size, with all things being equal between the calipers. That is a fact.
- Changing out your 5 to 10 year old brake fluid with new fluid will improve your braking performance. Thats a fact.
- Change out your 30 year rubber lines with new rubber lines or aftermarket stainless steel braided lines will improve your braking performance. That is a fact.
- Rebuilding your 30 year old stock brake system correctly with quality replacement parts, will improve your braking performance. That is a fact.
- Replacing your 30 year old stock brake system with a big brake system will improve your braking performance. That is a fact.
- Going to a lighter wheel, all other things being equal, will improve your braking performance. Fact
- Reducing your cars weight will improve your braking performance. Fact
If you go up on rotor size, you go up in weight, if using production type rotors. Is it possible that this weight increase could actually decrease braking performance? Yes, it is possible.
If you put a caliper that had a larger piston area on CTS-V or C4 HD brakes, with all other things about the caliper being equal, braking will improve because you will have better clamping force.
IF you put a caliper that had a larger piston area on any brake system, with all other things about the caliper being equal, your stopping will be better.
Brake fade can be overcome with the correct pad selection. Brake fade on a daily driver will be NON existant in most situations when drivng normally. 60 to 0 brake testing is a test for fade. I agree that a larger rotor will dissipate the heat better reducing brake fade until the larger rotor is saturated with heat also. On a daily driver, brake fade is not an issue unless you are pushing the brakes to its limits which is hard to do on the street. If it is a track car, you will want to change out the pads to a more aggressive pad to handle the heat. If the CTS-V or C4 HD pads that are good on the street are used on the track, you will have brake fade if you are pushing the braking limits.
More piston area is better, all other things about the caliper being equal.
Larger diameter rotor is better than a 10.5" rotor because you have better leverage.
Choose the pad for the driving situation. Street pads for daily driving. Track pads for the track.
Choose the best tire for your driving situation. Street car may want a 400-500 UTQG for long lasting wear. Track car may want to go with a 0-200 UTQG. The lower UTQG number will brake better on a dry track.
Last edited by manualbrakes.com; 11-18-2016 at 03:54 PM.
11-18-2016, 06:31 PM
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Re: Brake Caliper options
Not really. A car with weak brakes and poor stopping distance can easily lock up tires because the bias is wrong. Improve bias and all of a sudden those brakes might not even lock up but the car will have a much shorter stopping distance.
Last edited by QwkTrip; 11-18-2016 at 06:54 PM.
11-18-2016, 06:55 PM
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Re: Brake Caliper options
#1 - not necessarily. Many cars have brake systems inadequate for the stock brakes to stop the car quicker with stickier tires in the same size. An example is the Fox Mustang or the 3rd gens with 10.5" front brakes.
#2 - yes in most cases, but it can also lead to earlier lockup if it crosses the threshold where the wheels come too light. Obviously not the case for modern ABS cars.
#3 - Depends on where you remove the weight. Take too much off the front end, bias goes out of wack - it will not transfer weight properly. Same for taking too much off the rear - think unloaded S10 under hard braking. Sure you can adjust the front:rear braking bias, but since the front tires do 70% of the braking, it can hurt performance in an extreme situation. Rear and mid engine cars suffer from this - too little weight on the front axle, plus they usually run narrow tires up front leads to unimpressive stopping in most cases - although the rear bias will make the car feel better under extreme braking. Why doesn't a Miata stop from 60 in 75 feet? Becuase weight matters less than we realize in braking.
#2 - yes in most cases, but it can also lead to earlier lockup if it crosses the threshold where the wheels come too light. Obviously not the case for modern ABS cars.
#3 - Depends on where you remove the weight. Take too much off the front end, bias goes out of wack - it will not transfer weight properly. Same for taking too much off the rear - think unloaded S10 under hard braking. Sure you can adjust the front:rear braking bias, but since the front tires do 70% of the braking, it can hurt performance in an extreme situation. Rear and mid engine cars suffer from this - too little weight on the front axle, plus they usually run narrow tires up front leads to unimpressive stopping in most cases - although the rear bias will make the car feel better under extreme braking. Why doesn't a Miata stop from 60 in 75 feet? Becuase weight matters less than we realize in braking.
- ANY brake system will have better stopping distances with stickier tires, all other things being equal. That is a fact.
- Going to a lighter wheel, all other things being equal, will improve your braking performance. Fact
- Reducing your cars weight will improve your braking performance. Fact
11-18-2016, 07:18 PM
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Re: Brake Caliper options
OK, I didn't think this would escalate like this. I apologize. I did not and do no intend to bash big brake conversion and I hope I didn't come across that way. Yes, a 10.5" rotor is one of the smallest especially on a performance car. Yes, a 10.5" rotor will heat soak easier and induce fade easier.
No one thought your bashing bigger brakes.
If we go back to the original post, they are looking for calipers. Best option for a stock system is a bigger bore caliper, but the limitation to most braking systems is away's going to be the tires first. A stock caliper will do the job effectively on a stock system with pads that are for what the driver needs. If the original poster wants big brake system, then there are many options to choose from.
Best option? I wouldnt agree. Best option for increasing clamping force and PSI at the expense of longer travel and a softer pedal? Yes. Do you need too increase clamping force? Stock brakes will lock up without a big bore caliper. Why increase it? Maybe you don't want to throw on 17x10 wheels with R compound tires to baindaid locking up the tires.
If you go up on rotor size, you go up in weight, if using production type rotors. Is it possible that this weight increase could actually decrease braking performance? Yes, it is possible (thickness and material). Im not an engineer, but I would say leverage from a larger diameter would outweigh the performance decrease of the difference in weight. Again I am not an engineer.
If you put a caliper that had a larger piston area on CTS-V or C4 HD brakes, with all other things about the caliper being equal, braking will improve because you will have better clamping force. Will still lock up at the same pressure, same applies for pedal travel and softness.
IF you put a caliper that had a larger piston area on any brake system, with all other things about the caliper being equal, your stopping will be better. Again, wrong your clamping force/psi will be greater. Not better.
Brake fade can be overcome with the correct pad selection. Brake fade on a daily driver will be NON existant in most situations when drivng normally. 60 to 0 brake testing is a test for fade. I agree that a larger rotor will dissipate the heat better reducing brake fade until the larger rotor is saturated with heat also. On a daily driver, brake fade is not an issue unless you are pushing the brakes to its limits which is hard to do on the street. If it is a track car, you will want to change out the pads to a more aggressive pad to handle the heat. If the CTS-V or C4 HD pads that are good on the street are used on the track, you will have brake fade if you are pushing the braking limits. Eh, yes and no. Some pads resist fade better than others. It can not be overcome on a system that's not designed for the task. Its not hard to do on the street, two consecutive stops from 60-0 there will be a difference in performance. Exponentially worse the smaller the rotor/pad combo. CTS-V stock brembo pads actually perform pretty well on the track. They dust a lot, and sometimes make noise, but they also perform well on the street.
More piston area is better, all other things about the caliper being equal.
I don't know why you keep saying this.
Larger diameter rotor is better than a 10.5" rotor because you have better leverage. It is better for performance sure, you will have increased leverage with no change in pedal travel.
Choose the pad for the driving situation. Street pads for daily driving. Track pads for the track. Why? I have Hawk HP+ pads they perform great on the street. I dont track my car but according to reviews they perform great on the track. I haven't every daily driven my car, but its a street car. Honestly with the youngest of our cars being 25 years old I am not convinced many people here do.
Choose the best tire for your driving situation. Street car may want a 400-500 UTQG for long lasting wear. Track car may want to go with a 0-200 UTQG. The lower UTQG number will brake better on a dry track.
I wont comment on this
No one thought your bashing bigger brakes.
If we go back to the original post, they are looking for calipers. Best option for a stock system is a bigger bore caliper, but the limitation to most braking systems is away's going to be the tires first. A stock caliper will do the job effectively on a stock system with pads that are for what the driver needs. If the original poster wants big brake system, then there are many options to choose from.
Best option? I wouldnt agree. Best option for increasing clamping force and PSI at the expense of longer travel and a softer pedal? Yes. Do you need too increase clamping force? Stock brakes will lock up without a big bore caliper. Why increase it? Maybe you don't want to throw on 17x10 wheels with R compound tires to baindaid locking up the tires.
- ANY brake system will have better stopping distances with stickier tires, all other things being equal. That is a fact. Sure is, if the tires are your weak link. Don't stop there, so will lowering the CG, and tuning the suspension.
- Going to a larger rotor increases leverage to stop the car better with the same piston area. That is a fact. Sure is
- Going to a larger rotor will reduce fade until the rotor is saturated with heat and the pad is not designed for the heat. Fact Okay
- Going to a caliper with a larger piston area for more clamping force will improve braking performance regardless of rotor size, with all things being equal between the calipers. That is a fact. Not if you can lock up the rotor already, it will still lock up at the same PSI
- Changing out your 5 to 10 year old brake fluid with new fluid will improve your braking performance. Thats a fact. Okay
- Change out your 30 year rubber lines with new rubber lines or aftermarket stainless steel braided lines will improve your braking performance. That is a fact. Braided lines generally will improve clamp force, reduce travel and firm the pedal, by eliminating expansion
- Rebuilding your 30 year old stock brake system correctly with quality replacement parts, will improve your braking performance. That is a fact. If they are damaged or out of spec.
- Replacing your 30 year old stock brake system with a big brake system will improve your braking performance. That is a fact. If its built and installed correctly.
- Going to a lighter wheel, all other things being equal, will improve your braking performance. Fact Ill agree
- Reducing your cars weight will improve your braking performance. Fact
If you go up on rotor size, you go up in weight, if using production type rotors. Is it possible that this weight increase could actually decrease braking performance? Yes, it is possible (thickness and material). Im not an engineer, but I would say leverage from a larger diameter would outweigh the performance decrease of the difference in weight. Again I am not an engineer.
If you put a caliper that had a larger piston area on CTS-V or C4 HD brakes, with all other things about the caliper being equal, braking will improve because you will have better clamping force. Will still lock up at the same pressure, same applies for pedal travel and softness.
IF you put a caliper that had a larger piston area on any brake system, with all other things about the caliper being equal, your stopping will be better. Again, wrong your clamping force/psi will be greater. Not better.
Brake fade can be overcome with the correct pad selection. Brake fade on a daily driver will be NON existant in most situations when drivng normally. 60 to 0 brake testing is a test for fade. I agree that a larger rotor will dissipate the heat better reducing brake fade until the larger rotor is saturated with heat also. On a daily driver, brake fade is not an issue unless you are pushing the brakes to its limits which is hard to do on the street. If it is a track car, you will want to change out the pads to a more aggressive pad to handle the heat. If the CTS-V or C4 HD pads that are good on the street are used on the track, you will have brake fade if you are pushing the braking limits. Eh, yes and no. Some pads resist fade better than others. It can not be overcome on a system that's not designed for the task. Its not hard to do on the street, two consecutive stops from 60-0 there will be a difference in performance. Exponentially worse the smaller the rotor/pad combo. CTS-V stock brembo pads actually perform pretty well on the track. They dust a lot, and sometimes make noise, but they also perform well on the street.
More piston area is better, all other things about the caliper being equal.
I don't know why you keep saying this.
Larger diameter rotor is better than a 10.5" rotor because you have better leverage. It is better for performance sure, you will have increased leverage with no change in pedal travel.
Choose the pad for the driving situation. Street pads for daily driving. Track pads for the track. Why? I have Hawk HP+ pads they perform great on the street. I dont track my car but according to reviews they perform great on the track. I haven't every daily driven my car, but its a street car. Honestly with the youngest of our cars being 25 years old I am not convinced many people here do.
Choose the best tire for your driving situation. Street car may want a 400-500 UTQG for long lasting wear. Track car may want to go with a 0-200 UTQG. The lower UTQG number will brake better on a dry track.
I wont comment on this
Last edited by blackbmagic; 11-18-2016 at 07:26 PM. Reason: Posted chart
11-18-2016, 07:46 PM
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Re: Brake Caliper options
I keep seeing that spreadsheet posted in various threads. The values in the results column are incorrect because the wrong assumptions were made.
11-18-2016, 09:37 PM
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Re: Brake Caliper options
JOriginally Posted by malibudave View Post
OK, I didn't think this would escalate like this. I apologize. I did not and do no intend to bash big brake conversion and I hope I didn't come across that way. Yes, a 10.5" rotor is one of the smallest especially on a performance car. Yes, a 10.5" rotor will heat soak easier and induce fade easier.
No one thought your bashing bigger brakes.
Awesome
If we go back to the original post, they are looking for calipers. Best option for a stock system is a bigger bore caliper, but the limitation to most braking systems is away's going to be the tires first. A stock caliper will do the job effectively on a stock system with pads that are for what the driver needs. If the original poster wants big brake system, then there are many options to choose from.
Best option? I wouldnt agree. Best option for increasing clamping force and PSI at the expense of longer travel and a softer pedal? Yes. Do you need too increase clamping force? Stock brakes will lock up without a big bore caliper. Why increase it? Maybe you don't want to throw on 17x10 wheels with R compound tires to baindaid locking up the tires. Best option is the big bore caliper if you need it. Do you need it? Probably not. Brakes lock up because the tires loose adhesion. Tires are the limitation to a brake systems full potential.
Going to a caliper with a larger piston area for more clamping force will improve braking performance regardless of rotor size, with all things being equal between the calipers. That is a fact. Not if you can lock up the rotor already, it will still lock up at the same PSI. Actually it will lock up at a lower PSI, because your clamping force is greater at the same PSI. Pedal travel increases because of volume of fluid needed to fill a caliper with a larger piston area is greater. That being said, all third gen F-bodies came with a step bore master cylinders from the factory because they had low drag calipers, so this becomes a non issue if you are increasing piston area and keeping the step bore master cylinder as part of the system, because the step bore master cylinder can handle the volume without an increase in pedal stroke.
If you go up on rotor size, you go up in weight, if using production type rotors. Is it possible that this weight increase could actually decrease braking performance? Yes, it is possible (thickness and material). Im not an engineer, but I would say leverage from a larger diameter would outweigh the performance decrease of the difference in weight. Again I am not an engineer. It's like a wheel. A larger diameter heavier wheel will have longer braking distances, All other things being equal. It has inertia and your calipers will have to clamp harder to get them to stop. Another reason to have a caliper with a larger piston area. Yes you have greater leverage, but you also have more weight further out from the center of the hub.
If you put a caliper that had a larger piston area on CTS-V or C4 HD brakes, with all other things about the caliper being equal, braking will improve because you will have better clamping force. Will still lock up at the same pressure, same applies for pedal travel and softness. Like I wrote above, it will lock at a lower pressure because it will have the same clamping force at a lower PSI as a caliper with a smaller piston area at a higher PSI. Longer pedal stroke comes from the master cylinder having to supply more volume of brake fluid to the a caliper with a larger piston area.
IF you put a caliper that had a larger piston area on any brake system, with all other things about the caliper being equal, your stopping will be better. Again, wrong your clamping force/psi will be greater. Not better. Greater actually equals better.
Brake fade can be overcome with the correct pad selection. Brake fade on a daily driver will be NON existant in most situations when drivng normally. 60 to 0 brake testing is a test for fade. I agree that a larger rotor will dissipate the heat better reducing brake fade until the larger rotor is saturated with heat also. On a daily driver, brake fade is not an issue unless you are pushing the brakes to its limits which is hard to do on the street. If it is a track car, you will want to change out the pads to a more aggressive pad to handle the heat. If the CTS-V or C4 HD pads that are good on the street are used on the track, you will have brake fade if you are pushing the braking limits. Eh, yes and no. Some pads resist fade better than others. It can not be overcome on a system that's not designed for the task. Its not hard to do on the street, two consecutive stops from 60-0 there will be a difference in performance. Exponentially worse the smaller the rotor/pad combo. CTS-V stock brembo pads actually perform pretty well on the track. They dust a lot, and sometimes make noise, but they also perform well on the street. I'll disagree. A pad selection can overcome a system that is not designed for the task. It will be at the expense of chewing up rotors, overheating the calipers, and most likely pushing the brake fluid to the boiling point. If you are doing this a lot, then upgrade to a brake system designed for the task.
More piston area is better, all other things about the caliper being equal.
I don't know why you keep saying this. I keep saying this because its true.
Larger diameter rotor is better than a 10.5" rotor because you have better leverage. It is better for performance sure, you will have increased leverage with no change in pedal travel. Exactly.
Choose the pad for the driving situation. Street pads for daily driving. Track pads for the track. Why? I have Hawk HP+ pads they perform great on the street. I dont track my car but according to reviews they perform great on the track. I haven't every daily driven my car, but its a street car. Honestly with the youngest of our cars being 25 years old I am not convinced many people here do. Daily driving is maybe a stretch. Street cruising may be a better term. I am convinced that not all f-body owners want or need to spend hundreds, maybe thousands of dollars on brakes. They may just want to cruize, drag race, or don't have the money to spend on a bigger brake system.
I am interested on how your brake setup and pads perform on the track. Sounds like it would do well.
Choose the best tire for your driving situation. Street car may want a 400-500 UTQG for long lasting wear. Track car may want to go with a 0-200 UTQG. The lower UTQG number will brake better on a dry track.
I wont comment on this. Why not? You hit all the other bullet points above
OK, I didn't think this would escalate like this. I apologize. I did not and do no intend to bash big brake conversion and I hope I didn't come across that way. Yes, a 10.5" rotor is one of the smallest especially on a performance car. Yes, a 10.5" rotor will heat soak easier and induce fade easier.
No one thought your bashing bigger brakes.
Awesome
If we go back to the original post, they are looking for calipers. Best option for a stock system is a bigger bore caliper, but the limitation to most braking systems is away's going to be the tires first. A stock caliper will do the job effectively on a stock system with pads that are for what the driver needs. If the original poster wants big brake system, then there are many options to choose from.
Best option? I wouldnt agree. Best option for increasing clamping force and PSI at the expense of longer travel and a softer pedal? Yes. Do you need too increase clamping force? Stock brakes will lock up without a big bore caliper. Why increase it? Maybe you don't want to throw on 17x10 wheels with R compound tires to baindaid locking up the tires. Best option is the big bore caliper if you need it. Do you need it? Probably not. Brakes lock up because the tires loose adhesion. Tires are the limitation to a brake systems full potential.
Going to a caliper with a larger piston area for more clamping force will improve braking performance regardless of rotor size, with all things being equal between the calipers. That is a fact. Not if you can lock up the rotor already, it will still lock up at the same PSI. Actually it will lock up at a lower PSI, because your clamping force is greater at the same PSI. Pedal travel increases because of volume of fluid needed to fill a caliper with a larger piston area is greater. That being said, all third gen F-bodies came with a step bore master cylinders from the factory because they had low drag calipers, so this becomes a non issue if you are increasing piston area and keeping the step bore master cylinder as part of the system, because the step bore master cylinder can handle the volume without an increase in pedal stroke.
If you go up on rotor size, you go up in weight, if using production type rotors. Is it possible that this weight increase could actually decrease braking performance? Yes, it is possible (thickness and material). Im not an engineer, but I would say leverage from a larger diameter would outweigh the performance decrease of the difference in weight. Again I am not an engineer. It's like a wheel. A larger diameter heavier wheel will have longer braking distances, All other things being equal. It has inertia and your calipers will have to clamp harder to get them to stop. Another reason to have a caliper with a larger piston area. Yes you have greater leverage, but you also have more weight further out from the center of the hub.
If you put a caliper that had a larger piston area on CTS-V or C4 HD brakes, with all other things about the caliper being equal, braking will improve because you will have better clamping force. Will still lock up at the same pressure, same applies for pedal travel and softness. Like I wrote above, it will lock at a lower pressure because it will have the same clamping force at a lower PSI as a caliper with a smaller piston area at a higher PSI. Longer pedal stroke comes from the master cylinder having to supply more volume of brake fluid to the a caliper with a larger piston area.
IF you put a caliper that had a larger piston area on any brake system, with all other things about the caliper being equal, your stopping will be better. Again, wrong your clamping force/psi will be greater. Not better. Greater actually equals better.
Brake fade can be overcome with the correct pad selection. Brake fade on a daily driver will be NON existant in most situations when drivng normally. 60 to 0 brake testing is a test for fade. I agree that a larger rotor will dissipate the heat better reducing brake fade until the larger rotor is saturated with heat also. On a daily driver, brake fade is not an issue unless you are pushing the brakes to its limits which is hard to do on the street. If it is a track car, you will want to change out the pads to a more aggressive pad to handle the heat. If the CTS-V or C4 HD pads that are good on the street are used on the track, you will have brake fade if you are pushing the braking limits. Eh, yes and no. Some pads resist fade better than others. It can not be overcome on a system that's not designed for the task. Its not hard to do on the street, two consecutive stops from 60-0 there will be a difference in performance. Exponentially worse the smaller the rotor/pad combo. CTS-V stock brembo pads actually perform pretty well on the track. They dust a lot, and sometimes make noise, but they also perform well on the street. I'll disagree. A pad selection can overcome a system that is not designed for the task. It will be at the expense of chewing up rotors, overheating the calipers, and most likely pushing the brake fluid to the boiling point. If you are doing this a lot, then upgrade to a brake system designed for the task.
More piston area is better, all other things about the caliper being equal.
I don't know why you keep saying this. I keep saying this because its true.
Larger diameter rotor is better than a 10.5" rotor because you have better leverage. It is better for performance sure, you will have increased leverage with no change in pedal travel. Exactly.
Choose the pad for the driving situation. Street pads for daily driving. Track pads for the track. Why? I have Hawk HP+ pads they perform great on the street. I dont track my car but according to reviews they perform great on the track. I haven't every daily driven my car, but its a street car. Honestly with the youngest of our cars being 25 years old I am not convinced many people here do. Daily driving is maybe a stretch.
Street cruising may be a better term. I am convinced that not all f-body owners want or need to spend hundreds, maybe thousands of dollars on brakes. They may just want to cruize, drag race, or don't have the money to spend on a bigger brake system. I am interested on how your brake setup and pads perform on the track. Sounds like it would do well.
Choose the best tire for your driving situation. Street car may want a 400-500 UTQG for long lasting wear. Track car may want to go with a 0-200 UTQG. The lower UTQG number will brake better on a dry track.
I wont comment on this. Why not? You hit all the other bullet points above
