C4Scoreand7YearsAgo

I'm new to road racing and I'm humbly seeking advice about what I should do with my braking system before I hit the track again. I've done one event and will continue to do more in the future. What should I do to my brake system to make it as reliable as possible while I'm learning how to drive on the track? Its a '92, so its getting up there in age. I have fresh carbotech pads, high temp fluid, and I just ordered some Earl's stainless lines, but what else? I'm trying to spend my money on safety before speed at this point in the game.

Sidney004

I presume you are running the stock 12" brakes and not the upgraded
13" J55's. If that is the case, I would scour the C4 Parts Forum and be on lookout for the J55 abutement brackets, calipers and rotors and buy a DRM bias spring for your next upgrade. The cost for used parts should be pretty cheap($150-$200.) I would also get some Speedbleeders, but right now just run what you got, should be OK.

CHJ In Virginia

I would recommend that you install a set of coolinng ducts for the front brakes. Bringing in cool air to keep temps down will go a long way towards system reliability and safety.

jaa1992

I race a 92 and am now at the point where my J55's are marginal.
I can brake from 120/130 to 50 (Road Atl back straight to 10A) on Carbotech XP12/10 between the 200 and 100 marker.
I'm at 3500 lbs (heavy) competition weight.
I use regular old valvoline Syntec brake fluid.

1991Z07

I agree with both of the above posts...

I'm making ducts for mine using the turn signal locations in the front bumper to feed them. It is easy to convert back over to street use as well...3 screws and then set the ducts into the well under the headlights. I plan on putting fans in the ducts so I can leave them on when in the pits to cool the brakes after a stint.

Cooler brakes will let you run longer stints, and will be less wear & tear on the brake components. Piston seals get fried pretty quick without some good cooling on the brakes.

I'd also look at upgrading your cooling system. I put a Ron Davis 4-core in my '91 with an integrated cooler for the oil. I used an adapter plate above the oil filter and ran -10 lines to the radiator. My water & oil stay about 210-230 degrees when tracking in the heat of Texas summers.

mrc24x

It sounds like you're starting in the right place. J55's are a cheap upgrade if you want an improvement over the std setup.

Take a look at the AP racing calipers from Essex Parts if you are looking at a permanent solution. (I have the adapter brackets if you're interested).

Forgot to add the link...

http://www.essexparts.com/shop/compe...0-caliper.html


Matt

Kubs

The J55s are a good cheap upgrade to start, and cooling is very very important no matter what type of brakes you run. Also, the correct pad compound can help keep the brakes from fading with heat. A good fluid is also a simple fix. I use Amsoil DOT 4 600 brake fluid as it has a very high dry and wet boiling point. It has worked great on my C4. You can PM me if you want to try some.

http://www.amsoil.com/storefront/bf4.aspx

ScaryFast

For your first few events you will be fine. Good pads, good fluid, good rotors. You're not going to have overheating or braking problems in your second event. Lots of people will tell you that your car will explode after one lap if you don't turn it into a fully race prepped machine...that is fiction. If it is your second event ever, try a few more and see if you like this sport before spendnig a ton of money on upgrades you may not need.

Yes, these are trouble spots for the C4. Yes, once you start getting faster you will probably need to upgrade. But for now just relax and have fun. Learn to drive your car in that environment. Keep an eye on your temps and moniter your brake pedal feel. If it gets soft after a few laps, take it easy to cool the car down.

jaa1992

My first few events were in a 1988 AUTOMATIC Corvette with jl9 brakes (the small ones) and PFZ brake pads.

Aardwolf

Mine too! Overheated the pads in two laps lol

ErnieN85

look into converting to C5 brakes Vette brakes in Florida makes a kit

C4Scoreand7YearsAgo

Thanks for the advice. Sounds like brake ducts and J55 calipers are next on my list for now. I have a couple of track days coming up, so I'll see how it goes. What about the master cylinder? Should I rebuild it or replace it??? It has only 49K miles, but its 19 years old, so I assume it's time to do something.

jaa1992

What color is your brake fluid a week after you flush it?
I was flushing almost every event to get rid of the grey fluid until I replaced all 4 calipers and the master. Now its a quick bleed after each event and twice a year flush (twice a year cause I'm weird)

To the poster using the turn signal area to get air. I assume you are using a naca duct of some size. What did you find that fits and has a 3" outlet?

1991Z07

I'm having a sheetmetal shop make them up for me. I have not had a chance to get in there and start on it yet. I'm making a direct-fit replacement for the front turn signal assemblies AND the side marker ones. There isn't enough room to bring 3" through the space that the bumper lighting wires run through, so I was going to do (2) 2" or 2.5" ducts (one from each location). I plan on making a backing plate for the rotors and feed those ducts into it. I MIGHT use the frame rails like Callaway did for the turbos to route the air...not sure yet. Clearance is an issue with the ducting...so the cleaner I can do it the happier I'll be.

I need to get the bloody thing running again first...should have the rest of my intake back by the end of the week.

I've thought about this pretty hard for a while now. I've not had it to the track for >5 years...getting the itch again and want to make sure I'm good for the 427 SBC that will be finished in the next few months. I'll probably change out the brakes to something better, just not sure what yet. I've looked at the AP's, Brembo Porsche GT2/GT3 setups, and even considered C6 Z06 front/rear setups. It'll push me into RP class, and with the 650+ HP I'll have on tap with the new motor...stopping consistently will be a priority. I want it to feel like I dropped an anchor out the back when I hit the brakes...every time.

I need to get it on the lift and look under it to see where I can run things. I didn't like the kit I had for the front dam...it compromised ground clearance and the NACA ducts ripped off within a month of putting them on. Hence my thought about the turn signal areas.

The Panther

Humble seeker you should clarify that the front of your car is a 92, the passenger side is a 95, the driver side is an 89 and the rear is swiss circa 1970

ScaryFast

I like the marker light area (not possible for a streetable car, of course). I pulled them out and used some NACA ducts. Just heat 'em up so they're pliable, you can make them fit without compromising inlet size. If interested, I can get pics later. My car is not stored at home...

corvette95

I am in the same boat, are you c4's guys running with the fendwells in or out? Wouldnt the brakes get more air with the fenderwells (the front two) cut out?

Aardwolf

I ran with them hole sawed for a few years and took them out last year. Didn't notice any difference but have lots of OPR and stones in the nose now.

jaa1992

I had a piece of OPR fly up and go though the upper inner fender!

Sidney004

I have found that one of the major improvements in cooling are the wheels. When I switched from the restritive 17" sawblades to 18" Z06 Speedlines, a majority of my overheating issues disappeared. I attribute it to better cooling thru the wheel as well as increased gap between the wheel and the brake.