Armada95

Hello, I have a 91 Camaro RS, I'm looking to upgrade the brakes to handle the power of my newly build 350 (370 ish HP) I will be dropping into it, now I'm seeing all these LS1's and C# upgrade kits but they all say for 16 in+ rims and are fairly expensive, is there any upgrades I could do for a reasonable cost with 15" rims? My rims are aftermarket mags and are pretty nice, I don't really want to get rid of them, im also looking for bolt on upgrades or very slight modifications, I don't want/have the skills to get into fabricating special brackets/mounting stuff.


Any help or advice will be great.


Thanks

Base91

iTrader: (1)

You're really limiting yourself sticking with 15" rims. Not to mention the tire selection. You can get the rear 1le brakes inside a 15" rim. Maybe the front too. However, what tires will you be using? You may find the brakes you have are OK with the tires you have.

Armada95

Well right now the tires on them are the completely wrong sizes, (235/65/15 in the rears and 205/65/15 in the fronts) I'm looking at getting these, http://www.beggstire.com/s/search/ti...ort/popularity but I haven't gotten around to checking other tire places, at this point in time my brakes need a serious overhaul (I cant even lock the wheels up in dry conditions).

paul_huryk

While there are a few brake kits on the market to fit under 15" wheels, you should seriously consider moving up in wheel size to accommodate a larger brake system.

With that amount of HP (if you are close to your estimate), you should look to get a 13" brake kit and 17" wheels with 275-40-17 tires. You are going to need that much brake and tire to keep the car under control.

Armada95

If that is the case is there any kits out there that's fairly inexpensive? 1k+ is way too much for my blood.

gearheadotaku

iTrader: (1)

A good quailty pad and shoes with proper adjustment can work well. (fresh fluid too). Are you going to the track (Road course) or just cruising the strip?

Willwood makes a nice caliper set for the front that works with stock type rotors and pads for under $400.

Armada95

Its mainly going to be a Driver/Toy not really a Drag car or track car, just a car with good power, I've been looking around at that LS1 Conversion and it doesn't seem that difficult, but I was wondering, instead of modifying the Gen 3 Spindle couldn't I just buy the entire spindle/brake setup from a Gen 4 Camaro? or would it not be a bolt up option.

PAFORM350

Armada95

So I've decided to do the LS1 Swap since it seems fairly inexpensive, just need to do some Fab work (form what iv seen its not too hard) But I got a question, I was looking at that "Brake Upgrade and Wheel fitment" sticky, and some people were saying the LS1 swap Wont fit in 15" rims but some say it will fit in some rims, now these are the style of rims I have on the car, http://www.toyotaminis.com/forum/att...deas-5hole-jpg, I DO not know if its the 15x7 or 15x8 at this point in time, does anyone know about these kinds of wheels and if it will clear the LS1 swap" I was told they were centerlines, but the Wheel says "Mags" on the center cap. Any ideas? or should I just go get some 16" Rims

Base91

iTrader: (1)

If you're going to change rims go straight to 17" as suggested. Good tire selection and plenty of room to clear any but the biggest of brake upgrades. As for cost. I got the rear 1le (11.6") set up for about $150 total from a couple of TGO members and the C5 corvette (almost 13") set up including hubs, brackets, calipers, rotors, braided lines etc. etc. for less than $400. Parts here and there from TGO members when I saw deals. If you can't wait and want all shiny and new in one shot then you're looking at the $1k plus route.

Ron U.S.M.C.

As mentioned, a 13" brake kit and 17" wheels with 275-40-17 tires will keep him on the road and for anyone wanting to play hard it is all but a necessity with these cars.....
After that I would look into getting a L.S.D./Posi

Armada95

I Plan on switching it to a Posi in time, im just getting the rest of the car "sound" before replacing something that technically isn't broken, my brakes are doggish, suspension is in need of work, and steering wobbles at high speed, that's my priority to fix before I get even close to putting a high power motor in lol, im just seeing if it would be worth upgrading the brakes now, or just do a normal brake job to restore the braking power of the stock brakes and worry about upgrading for the v8 when I go to put the v8 in, if the LS1 swap fits with my style/size of Rim ill most likely do that, but at this point in time I cannot afford to buy whole new rims and tires (tires not so much cause I need new tires anyways)

86firebird350

https://www.thirdgen.org/forums/brak...-ultimate.html
https://www.thirdgen.org/forums/brak...setup-aka.html

For a DD or weekend cruiser I would recommend the above. For serious braking power needs, I would do what has already been suggested (upgrade to 17" wheels so you can fit a bigger brake set up)

paul_huryk

I'm going to disagree with this suggestion.

Maybe in a car with 250hp or less it makes sense, but with the amount of power you are expecting, it is throwing money away. It will cost only a little more to get a 13" kit vs. stock upgrades, yet the results are huge. Only downside is the minimum 17" wheel and tires you will need.



[QUOTE=86firebird350;5897443]https://www.thirdgen.org/forums/brak...-ultimate.html
https://www.thirdgen.org/forums/brak...setup-aka.html

For a DD or weekend cruiser I would recommend the above. For serious braking power needs, I would do what has already been suggested (upgrade to 17" wheels so you can fit a bigger brake set up)[/QUOTE]

86firebird350

Paul, I respect your opinion on most topics and value your advice, but this is one area where we always seem to have differing opinions. I do think it's good advice to upgrade to bigger brakes, but only if you're going to get full use of them doing auto-x or the like. Horsepower does not dictate the braking power needed. It's HOW the car will be used. If this car was going to live it's life at the track doing events every weekend, ABSOLUTELY I would recommend bigger wheels/tires and brakes. But the OP stated this car will be used as a driver/weekend car, for which case I think the setup I posted is plenty capable. Heck, even an occasional pass down the drag strip would be fine for this setup since the brakes would only be used once and allowed to cool after each pass.

It looks like Armada95 has decided on the LS1 upgrade, so this debate seems moot now. Armada, I'm sure you'll be happy with the results, whatever you decide. Just about anything you do is an improvement over the factory setup.

Armada95

I was looking around at different brake systems/calipers, etc, and i came across these, http://www.wilwood.com/Calipers/Cali...0Dual%20Piston its states it would be a direct bolt up to most 68-96 vehicles. will it work with our cars? has anyone used these?

RBob

iTrader: (1)

Won't bolt up, they are the larger pre-metric calipers.

Howe Racing has some metric calipers that may work. Although I don't see much improvement coming from any stock-type replacement over the stock calipers.

Best things to do while retaining the stock brakes is to use good rotors and good street performance pads.

RBob.

Armada95

how so? both the stock calipers and these are non-metric, theres also these, http://www.wilwood.com/Calipers/Cali...o=120-11874-BK same style, different caliper

novaderrik

i had 15" Monte Carlo SS wheels on my Camaro with the LS1 brakes on the front, and i just had to grind down the fins on the caliper maybe .030" to get them to clear. not a bolt on, but a worthwhile upgrade from the craptastical 10.5" "metric" setup they used in these cars stock.

1991_RS

FWIW, the C4 (Non-HD) upgrade is supposed to fit 15" rims.

paul_huryk

There may be a 30ft difference in stopping from 60mph by using a 13" kit vs the stock 10.5" system - even if you buy the best OEM replacement parts available. Considering we all drive at 65mph+ on the highway - no reason to have underperforming brakes compare to the engine power and handling...

Armada95

After reading those 2 threads, that's something I've also considered doing...atleast until I get my v8 in and see if a upgrade is needed later on, now in those threads they were saying changing the Proportioning valve because the rear brakes are slacking, now on both threads it was with disc brakes in the rear....what about drums since I have drums in the rear or does it not matter?


(On a positive note I noticed my brake booster vacuum hose was rubbish, ad a very minor leak, not very noticeable at idle but def while braking, replaced that and my brakes work a bit better but still needs a brake job)

86firebird350

I have heard of guys putting the 1NCR5 spring in the proportioning valve of their rear drum cars. I don't really know enough about the differences between the two from a technical standpoint (line pressures, proportioning valves, clamping forces, etc.) to say whether it's a good idea or not.

sofakingdom

iTrader: (1)

People always like to ask this question (apart from all the noise about prop valve and all that) WITHOUT doing even the most minute mental effort first.

THIMK.... use your kidneys here...

You're talking about a 15" wheel. OK, half of 15" is 7½"; that's the distance between the center of the wheel hub and the inner surface of the tire bead. Got that number firmly in your head? Do we agree that that's a good starting point for measuring things, that is, an ABSOLUTE HARD OUTER LIMIT on the space available to work with?

OK, so then the wheels are maybe a total of ½" thick right there, so now you're down to 7" to the inside surface of the wheel. OK so far?

Then of course the inside of the wheel isn't a perfect cylinder; tends to be somewhat cone-shaped or to have various "steps" or other such features in it. Let's be generous and allow another ½" for such details. OK, so now we're down to 6½" from the center of the hub to the inside surface of the wheel.

So let's take a look at a caliper. It has some thickness where it fits over the top of the rotor; for strength, and if there's pistons on the other side, fluid passages. I can't recall seeing any calipers that could be considered an "upgrade" over stock that were much less than ¾" thick out there. OK, take away that, now you've got 5¾" left that you can put a rotor in.

But of course, the outside of the caliper can't rub on the inside of the wheel, and the inside of the caliper can't rub on the outside edge of the rotor; let's leave ¼" of clearance at each of those, total of ½" of clearance. Now you're down to 5¼" of rotor.

Butt weight... 5¼" radius = 10½" diameter.... and how big are stock rotors? Hmmm... I'm thinking I'm seeing a pattern develop here.

Now of course, the OE Saggy calipers don't have fluid passages or fins, and they're cast-iron besides, so they're a bit thinner where they fit over the caliper, maybe only ¼" thick; so that, plus the fact that stamped sheet steel wheels are a good bit thinner than cast alloy ones, and that gives enough clearance to allow them to go inside 14" wheels.

Given that THE STRONGEST WEAKNESS of the stock brakes in our cars is really the rotor diameter, and that therefore THE MOST EFFECTIVE upgrade is to increase th erotor diameter, not hard to see why getting rid of the tiny stock 15" low-perf wheels is pretty much an imperative, and why it's kinda pointless to talk about putting any kind of significant brake upgrades inside of that old stuff.

87350IROC

iTrader: (2)

Your assumptions are conservative. Per your math:

Wheel Size Max Rotor Size
16 11.5
17 12.5
18 13.5
19 14.5

Examples that contradict your assumptions:

16" wheel, 13" rotor


17" wheel, 14" rotor



19" wheel, 15.5" rotor


I'm not saying every xx" wheel will fit every xx" rotor. Some research needs to be done by the customer. The customer also needs to figure out what they are trying to get out of their brakes. Most people overlook how brake kits compare with respect to pedal feel. Both pedal travel and pedal effort.

John

sofakingdom

iTrader: (1)

Right; my assumptions are based on, ANY 15" wheel, ANY xx.x" rotor, ANY caliper, etc. And you're right, my assumptions are a bit on the conservative side; I get the ******* when I see my calipers less than 1/8" from my rotors, or less than 1/8" from the inside of the wheels. Others may be willing to take more risk, especially OEMs who have the resources to experiment. Shadetree hobbyists, not so much.

As always, there might be a few specific exceptions; but, the principle is what's important, more than the absolute numbers.

sofakingdom

iTrader: (1)

Oh, and I would add...

If my "math" (it's hardly even arithmetic AFAIAC, but I guess that's all in your POV) is in error, please point out where, and correct it so that we can quit having this same pointless post over and over again, and maybe the mods can take the good stuff out of all the posts and make a sticky out of it to eliminate the bandwidth waste.

novaderrik

from my own real world experience:

12" C4 Vette front brakes fit easily behind 15X7 70's GM Z/28 wheels with room to spare- like over 1/4" at the closest point.

F body LS1 12" front and rear disc brakes fit behind 15X7 80's aluminum Monte Carlo SS wheels. the front calipers are close on the fins, but they clear.

not my own experience, but i believe that on the short tracks and road courses the NASCAR Cup guys run 13" rotors with HUGE calipers with HUGE pads behind a 15X9.5 steel wheel..

bbc632

My set my friend has them I drove he's and there nice and don't brake the bank

Armada95

Whats the P/N for thoes calipers?

bbc632

Manufacturer's Part Number:140-12097-R I got them from summit racing.

87350IROC

iTrader: (2)

Some thoughts.

I highly doubt any wheel barrel out there is 1/2" thick. I will admit that I have not measured this on my own but I would imagine that the wheel is no more than 1/4" thick.

The thickness of the caliper over the rotor. I think 1/2" will be more typical than 3/4". Calipers seem to be optimized well in this dimension.

Finally the gap between the caliper and rotor and caliper and wheel. The calipers I play with typically have around 1/8" clearance between the rotor and the caliper. The typical minimum clearance for rotor to wheel is considered to be 3mm or 0.118" which is just about 1/8".

Obviously every different setup will have some different numbers. At the end of the day the particular wheel being used is just as important as the basic wheel diameter. And this doesn't even consider the clearance between the back face of the spokes and the outer face of the caliper. In many cases this is more critical than the rotor diameter. For instance the CTW wheel has TONS of clearance in this dimension. I would challenge someone to find a caliper that won't on this wheel. On the other hand, the OEM GTA wheels are very restrictive in this dimension.

John

Armada95

So after some extensive searching, I've discovered my wheels are Centerline Champ 500 Series 15 x 7.....Since some people have fit the LS1 brakes behind SOME 15" rims, not all ofc, does anyone know if it will fit behind these? Any luck with them? If not its no big deal, just getting as much information as I can.


Thanks

novaderrik

find someone local with a 98-02 F body and ask them if you can try one of your wheels on their car..