Me? Stainless split washers.


Ed

 

I am finally about to do the LS1 brake swap (there has been many postponements) and I was thinking about which proportioning valve would work best and this is what I came up with…

First I figured out the surface area of each brake setup:
The C4 and 1LE piston is 1.5 inches in diameter. So that’s 1.767 sq. inches of surface area per piston. So 1.767 (sq in of 1 piston) x 4 (pistons) = 7.068 surface area total.

The LS1 brakes are 1.75 inches in diameter, so that’s 2.405 sq. inches of surface area per piston. So 2.405 (sq in of 1 piston) x 4 (pistons) = 9.62 surface area total.

I never measured the size of the piston on the stock front brakes but I found in another thread that the stock brakes have a 2.375 inch piston. So 4.430 (sq in of 1 piston) x 2 (pistons) = 8.86 surface area total

Since the 1LE calipers actually have less surface area then stock calipers (1LE’s made up for by the larger caliper) GM probably routed more brake fluid to them in the 1LE proportioning valve then the stock proportioning valve. So following this pattern of thinking using the 1LE valve on LS1 brakes would transfer to much power to the fronts and the stock valve would be a better match.

Does anyone know the actual percent ratio of each valve? Or has anyone tried both valves on there LS1 setups?

Edit:
In the parts store the stock piston is listed as a 2.5 inch. If that is the case here is the revised version of the surface area for the stock piston.
2.5" = 4.909 (sq in of 1 piston) x 2 (pistons) = 9.818 surface area total

 

Also it would be really helpful if someone could scan up brake servicing pages out of a 98+ 4'th gen service manual.... I'll ask on camaroz28.com

 

Does anyone know how much parking cables and backing plates for an ls1 rear cost and where the best place to get them would be? I just scored all the rest of the parts rear calipers,rotors pads/shoes ect from an 00 camaro for 50 bucks. I plan on going back to the salvage yard to try and get the backing plates and parking cables. They wouldn't come off last time. The bolt holding the cross pin in the posi is rounded off. and the cables are almost impossible to get , as the car is sitting on it's floor pan.
Thanks,
Kory

 

www.tacreationsusa.com

Ed

 

Ed,
You have a PN for those bolts?

 

Already did....posted earlier in this thread, around the top of the page:


Ed

 

Hey Ed, weird thing...I ordered the bolts 10229606. I got two of them, as I still had 2 of them from the junkyard. No threadlock on them, however, these are flanged bolts, not just straight up bolts like the other two I pulled off the spindles. They go into the carriers fine although they look like they may be a little long.

I just helped my dad machine the brake surface off with a brake lathe tonight and my buddy is going to machine the rest off this thursday. The brackets are coming along, just too many irons in the fire. Wideband came in today, and I think I'm finally going to get the 3.70's in the 9-bolt tommorrow.

 

I noticed that too...the new bolts Dal sent me are not like the ones I pulled off another car, but I do like them better as they are flange head bolts and the ones from the car aren't. I don't know what's up with that. If they are a bit longer, take up the extra with a lockwasher to be safe.


Ed

 

Thanks for reposting Ed. This thread is so long that it is easy to miss things.

 

Luke (89 Iroc Z?),
I did similar calculations on piston area when trying to decide whether I should change my master cylinder. I believe I got the same piston area values you listed.
For proportioning valve, I would recommend you install an adjustable one then you can set it to what you feel is the optimum. If you ever decide to modify the rear brakes on your car, you will be able to adjust for that change as well. Most guys on the board don't seem to like the adjustable valves though, so I'm in the minority suggesting one. It's kind of suprising to me since a lot of guys have modified/changed/upgraded just about every part on their car except the proportioning valve.
Since I have the adjustable valve, I cannot offer any suggestions on what GM proportioning valve would be best. Keep in mind though that the clamping force generated by the caliper comes from the brake fluid pressure not the volume of fluid moving to the caliper. The fluid volume dictates how far the caliper piston(s) move for a given brake pedal travel. Also remember that a proportioning valve limits fluid pressure to the rear calipers not the fronts. The front calipers always get full brake pressure regardless of what proportioning valve you use. If my thinking is correct, the 1LE valve would give you less rear brake than the stock valve (for a given brake pedal pressure, the increased surface area of LS1 pistons generates more front caliper clamping force than the 1LE meaning the rear calipers could have more pressure and do more of the braking work than the 1LE valve will allow). Of course this all goes out the window unless you have the 1LE master cylinder and the 1LE rear brake setup. If you don't, then the front/rear brake ratio (bias) the 1LE valve will provide must be recalculated to consider your rear brake setup. See why the adjustable proportioning valve is such a convenient solution?

Chuck

 

I just scored a complete rear brake set up off of a 00 camaro today for 80 dollars. The only thing I wasn't able to get was the parking cables. By any chance will my stock 88 rear disk parking cables work?
Thanks,
Kory
btw I bought the front calipers, cages and all associated hardware exept the rotors for 50 bucks.

 

Well, Im up to like 540 miles on my setup. Several hard stops. I found a list of what size bolts require what torque, so i applied red loctite, and torqued em all down, and theyre still tight. Im running a 1LE prop valve on mine, but I can't say for sure what difference it made, but the car hardly dives at all, but i think spohn says the torque arm helps with that too...

 

Yup, Just have to open the eyelet a bit so it can go around the hook, you may also have to do a bit of rerouting, but other wise I believe it should work.

 

Thats great thanks for the info.
Kory

 

Yeah this happened on my 9 bolt to only damage thought was a little bit of material off my camaro aluminum rims. lucky for me. thanks for the tip to fix it.

 

All done!
Turned out great. Did not have any problems with the bumpstop and the banjo bolt on the caliper interfearing.

Cant wait to get it aligned to see what they and the new Bilstein's and Pro kit will do!

Yah I know I had to ruin it with my ugly mug..

 

Well I took it out for a spin, MAN these things stop GREAT. On a panic stop anything in the car ends up front . Night and day difference between the stock ones and these!

 

I know this has come up before but the thread is so long I couldn't find a real answer. I am going to install LS1 brakes on all corners and don't know which is the best proportioning valve. My car is originally drum rear. Any advice would be greatly appreciated. Thanks.

 

I have gone back over this thread, and maybe I missed it, but what pads is everyone using on these brakes? I am doing this conversion as part of my suspension rebuild and want a good pad for the street that can handle occassional heavy braking, but prefer something that will not dust too bad. I have searched the boards, and it seems that ceramics may be a good choice, but can't seem to find a definitive answer.

I am considering the NAPA ceramic pads, but before I put out that much for the ceramics, I would like to hear from anyone that has them or anything similiar. Bendix titaniums also seem to be a popular choice here for the stock brakes, but what about for the LS1's?.

 

I used the titaniums, dont have much milage on them yet but I do like them. Still have to get thru the break in material on them.

 

I used : from my previous post
edit: I see you have a 88, this one has a different thread pattern, won't work for you unless you re plum your lines.... Don't have the earlier valve #

 

Part number for the earlier prop is #14089496, mine was $55 shipped from Dal 2 yrs ago. Here's more prop valve info and part numbers:

http://www.ws6transam.org/1LEbrake.html#1LEfront

Ed

 

I don't think the 1LE valve will be the best choice for the LS1 setup. Just a few threads up I talk about it...
https://www.thirdgen.org/techbb2/sho...30#post1945869

Has anyone tried both valves on the LS1 setup?

 

I thought the prop valve only affects the rears, and the fronts get 100%

 

about pad choice, i am using raybestos quiet stop pads. they
work pretty good on the street and i have had them on the track a few times and the the dust wasn't too bad. i will probably step up to some " (insert color here) Stuff " pads when i get some slotted rotors.

 

Most of the LS1 guys I know like the stock LS1 pads for 'sprited' street driving and occational track time. When I had to replace the pads on my 02 SS I went with stockers. They are relatively low dust and have a very good grip. Also when you buy the pads you also get the copper anti squeak plates and bolts for the calipers. I plan on using LS1 stockers for my El Camino when I install these brakes.

EDIT - also for you guys that might interested in them you can get some stickers for the front calipers that say Camaro, Firebird or Trans Am. I have a set on my 02. You can get them from After Thoughts Auto For anyone that might be interested.

Here's a picture of them on my calipers.

 

Saw that site, and am interested, but wondering how they hold up though over time, with the brake heat and all? How long have you had them? I can read what the site says, but would like to hear from someone who has been running them for a while. What material are they made from, stainless? I have also seen vinyl decals for the same purpose, but again, wonder how they hold up over time.

 

Thought I read somewhere that the stock ones were a ceramic pad. Anyone know that for sure? Have PN's?

 

I have had them on my car for about 2.5 years now. This includes about 200 passes on the 1/4 mile and day of road racing at Buttonwillow. To give you an idea that day my brakes got so hot that I boiled my brake fluid and lost my brakes, shot off the road at about 50mph luckly it was all dirt. I think they are still holding up very well. What I did was use a high temp (500*) primer, about 2-3 very light coats. Then high temp gloss black, again 3-4 very light coats. 2-3 coats of high temp clear, applied the decals, and then 1 coat of clear. The material is a 'metal' material like what is used on sign posts not sure exactly what it is. Not sure how well vinyl would hold up.

 

Thanks for the info Poltergeist, sounds like longevity is not a problem at least with those metal ones.

 

This what I got from my parts file

98 (J65)____Pad kit front____18026165
98-00______Pad Kit front____18038574
99-02 (J65)__Pad kit front____18026298

98-99 (J65)__Pad kit Rear____12454972
98-00______Pad kit rear_____18039835
01-02 (J65)__Pad kit rear_____12454972
00 (J65)(1st design)__Pad kit rear__18038575
00 (J65)(2nd design)__pad kit rear__12454972


J65- Brake system,Power,Front and Rear disc

 

What is the difference between those three part numbers? I though the LS1 brakes were the same from 98-02.

 

That is the way they are broken down for the service kits. But here is something funny: when I just compared the separate parts they are the same part number. GM has the strangest way of doing things. I can try and post the pages when I get home tonight if you want.

 

Please do.

 

OK here you go, sizes of the pictures are 80~117k in size:

Front Brake picture

Front Brake parts list

Front Brake service kits

Rear Brake picture

Rear Brake parts list

Rear Brake service kits

 

Has anyone confirmed that the Ronal R15's will not fit the LS1 setup? Since they weren't available I planned on different rims, secured a 4th gen rear, and was planning a front LS1 swap.

Now that they're available again, if they will fit the LS1 setup, I'll get rid of the 4th gen rear and change plans..

Thanks,

Kevin D.

 

I talked to Gary about 13" front brakes on friday. He said 13" brakes would fit. I have ls1 brakes on my car now. I was thinking of upgrading to 13" c5 brakes Thats why I asked. He said it wouldn't be a problem.
Kory

 

I'm sure the LS1s would fit those wheels with no problems, the wheels are 17" so they're plenty big enough.

The more I mess with these brake upgrades, the more I like the C4 HDs and C5s over the LS1s...here's why:

First off, the LS1s are a tighter setup to fit up to the spindle...this has been addressed in this thread already. You have do to a lot of fit up, look at your clearance, disassemble, and grinding to both the brackets and spindles get them to really fit good;

Second, the calipers are getting well known for spreading out a bit when they're repeatedly used hard as they would be in road racing and Auto-X. This will cause the pads to wear unevenly...it's even talked about on the Monte Carlo SS forums and there's only a handful of those guys even running these brakes on those cars;

Third, both the C4 and C5 brackets have less interference with the spindle as I mentioned above;

Fourth, the 13" HDs and 12.75" C5s will give you a larger rotor which is what you want anyway....IMO, guys with 17" or larger wheels should run C5 brakes and nothing else.

Again this is just my opinion and the LS1 brakes do work well, but it's these little points that make me not like them as much as other setups out there.


Ed

 

Ed:

The above is why I asked. That's discussing the 17" Firehawk rims on page 1. Of course I don't believe he physically tried to mount them, but was just discussing the ID's.. I was planning on the C5 setup anyways, and it's even larger than the LS1..

Kevin D.

 

Baer PBR 13" brakes wont fit Firehawks without some grinding of the caliper. I haven't tried them, but others here have had to grind some of the fins down. IIRC, C5 brakes require more space then the PBRs, and do to the offset, the C5 calipers sit closer to the wheel spokes. LS1 should fit fine since its only a 12"

 

Also, dont forget Firehawks need spacers if your not using 1LE brakes. The C5 brakes use the stock 10.5 as a hub. I dont know if the added width of the rotor will be enough to supply the req clearance between the rim and tie rod. The C4HD use the 1LEs as hubs, so they will clear fine.

 

OH, Ok...I get it now. Unfortunately, I have no access to one of these R15/Firehawk wheels so I won't be able to find this answer. If the 13" HDs won't fit that wheel, then I can guarantee the C5s won't fit and if the spacer is needed to fit the Firehawks to anything other than 1LEs, my guess is the wheel will hit the LS1 caliper like it did on the GTA crosslace wheel.

I hope yours fit, Kory. If someone close has one of the wheels, I'll gladly drive over and fit up what brakes I have on hand.


Ed

 

Guys, I'd like to switch gears just a little. I haven't read this thread in awhile so pardon me if this has been hashed out already. We all know the C5's won't fit in stock 16" wheels, but I believe it's close enough that only minor grinding of the ribs will get you by. I know that many have urged against grinding the ribs, but I've done it and don't feel bothered at all. Some may remember that I ran into this problem with my 17" ROH ZS wheels. Here's a pic of the backside:



I'm not sure why they did this but I never noticed it until I had the new setup on. In any case, here's a pic of the calipers with the ribs ground down then painted black:



I believe that the stock 16" wheels have nearly 15.5" of clearance which seems to be a bit more than me. Of course, you guys can do what you want, but I wanted to let you know that someone had done some grinding on the C5 ribs with no ill effect.

--Aaron

 

Thats about what the back of the Firehawk rims look like with that step in right near the edge.

 

ok guys, here's some grinding:

Original front rotor:


Modded:









I have had 200+ trips to the track, and it's my daily driver, so no worries grinding on these bad boys...they'll hold up fine. You can even see on the rear calipers where the caliper bolts are coming through!


hope this eases some of your fears. I'm not the only one to do this either...theres a few of us that has had to do this to get the telstar wheels to fit these calipers. Have no fear, and bust out that grinder

 

alot of ls1 guys grind the calipers to fit 15" welds with no problems, and thats stopping 8 second cars with no problems

 

wlsmoku, I can understand grinding a little off of the caliper, but it appears to me by your pics that you ground completely through the casting on the rear calipers...am I right? I can't say I like that but it is your car. JMO...


Ed

 

no offense taken - I was expecting to catch hell from some peeps, but since I knew other peeps have done it, I thought it would be ok, and it has been...for a couple years of daily driving duties infact. It's not for everybody, and there is always a risk, but they are beefier than some people on this board are giving them credit for too

 

I understand...I was just surpised to see them taken that far. I sure won't give you hell for it... aren't most upgrades a bit of risk anyway? There's a few guys on other boards saying that the hubs we make aren't safe and can be broken if you hit them with a hammer... but what can't you break if you hit it enough with a hammer?

Ed