Hello !

Has anyone ever considered useing bigger brake discs with stock calibers ?

It wouldnt be too hard to machine adapters to move calibers 0,5" outboard and then just use 1" bigger disc with same thickness with aluminium hubs.

Is there any idea?

 

The $110 (US funds) J55 C4 calipers suk & $120 GS isn't much better. They bend open like a chinese C-Clamp under track conditions. Why bother? You can buy C5 calipers that work on a wider, meatier rotor that flows more air thru the vanes for about $150 ea. Simple spacers are used to install the C5 rotor and caliper. This is cheap. It results in better rotor heat dissipation and still allows 17" wheels.


[Modified by Rick93Z07, 10:08 AM 6/18/2003]

 

Check it out.
http://forums.corvetteforum.com/zerothread?id=581163

 

Why bother with the C5 kit, it sucks as well in heavy track applications.

 

So where is ur recommendation, your POSITIVE input to a solution? We all know the C4's r under braked.

Not everyone is pushing there cars to the very limit, as in "ORR", and not everyone can afford 4 piston Brembo's, or 6 piston Willwoods ! ! !

U r the only person on this forum, that I have noticed, with negative input regarding the C5 front brake upgrade. Then in another thread, u recommend that the C5 upgrade is the way to go from stock, not J55. ?????




[Modified by edsalinas, 7:09 AM 6/19/2003]

 

:iagree:

 

Some people value their lives more. When pressing the car hard at the track and you run out of brakes trying to slow from 100+ it makes you think.

I toss out what I have learned, take it for what it's worth. I only posted as Nick93Z07 brought up the fact of the C4 calipers spreading under track conditions, well the C5 caliper does the same thing.


I recomend the 84-87 guys go to the C5 setup, as it is a easier and cheaper upgrade for them. I recomended them to corvette0096 as I know the only hard use his brakes will see is slowing down from a 1/4 mile run.

 

from:larrybsp@aol.com Larry Stark

On my 90 race car I have a set DRM kit C5 front brakes with Hawk blue race pads. They work very well but had a soft pedal. I solved the problem by installing a master cylinder out of an F Body Camaro. I see
very little clam shell effect on the linings from the calipers opening up.
Both side linings are wearing as if the car had positive camber when it has lots of negative camber. I don't think the calipers are parallel to the rotors
even though the kit has nothing obvious that would cause them to be out of parallel. I use plenty of brake cooling air on the rotor and caliper and run Motul fluid. I can really get hard on the brakes for a 35 minute race and they
work great. Biggest problem is that linings are too thin so they wear out fast.
I have the shorter pistons for the calipers that came with the kit but you really don't gain much. FWIW. :cheers: :flag :steering:

 

Yes you all are right but i am just looking for a bigger brakes for filling up my wheels:) I have allready 13" grandsport brakes and i love the black calibers .I have a light car so no need to go brembos etc. I only need to know can i go bigger rotor with stock caliber?

 

If you don't track the car (as in road course use), the C5 brakes are a good upgrade, and as mentioned, they are inexpensive and can carry better rotors, not just larger diameter. Moving a caliper out only 0.500" is actually a lot more difficult than you might think. You'rebasically offsetting the caliper by the diameter of the mounting bolt. If you take a good look at it, you'll have a hard time making a simple bracket that's strong enough.

If you DO track the car, and you're hard on brakes as JeffVette and myself are, you'll want something bigger. I have a VERY light fully-upholstered Vette (last time I weighed it, it was 3050 wet), and brakes that are even remotely stock are WAY too small for track use. Then again, I'm hard enough on brakes that I've faded the Brembo Big Reds on a 2400 lb Porsche track car in under 10 minutes. I have never seen anyone who drives their '84-'87 harder than about 60-70% of the car's capability even THINK about running the stock early brakes at the track...they're just too small. Most of the folks I know who have run the GS brakes still have problems towards the end of a 20-25 minute run session.

 

Thank you, very clear, precise, and succinctly put.

 

The C5 calipers do gradually bend on-track. If you're gearing up for a season of SCCA T1 Competition, carry spares.

If you're doing a few amateur track days each year, it's a non-issue. Let's face it, two new C5 calipers are cheaper than a set of premium race pads. You might need to change them every 30-50 track days. When I'm running long-lasting street rubber and no trailering, I spend about $500 for every 2 day track event. You may need to invest $250 in calipers for every $10K worth of track time. Peanuts in relative terms.

 

As a quick side note, although the pads are larger, the stock C5 rotors are not a larger diameter than the GS rotors; they are actually slightly smaller. Click to see Pics from the Superior comparison-

Pads: http://www.superchevyperformance.com/misc/c4c5pads.jpg

Rotors: http://www.superchevyperformance.com/misc/c4c5rot.html

:chevy


[Modified by Midgetfist, 3:05 PM 6/19/2003]

 

I recomended them to corvette0096 as I know the only hard use his brakes will see is slowing down from a 1/4 mile run. [/QUOTE]

:yesnod:

 

Try http://www.dougrippie.com/

for starters. They sell C4 upgraded rotors that are 13 x 1.25, and it appears that you just need to use their "shorter caliper pistons" to make it work. Their prices seems pretty $$$ though, just an idea.

 

there are pros and cons to every bench racing session. My Corvette in SCCA ITE trim weighs in at 3025#. I run the C5 front calipers and rotors. The key
I discovered to make them last a 35 minute race is you have to really cool them. I have an elaborate set of ducts that picks up high pressure air under the nose and ducts it straight to the rotor AND caliper. Before I did this I burned up a set of C5 rotors, calipers and pads each race. I also run 17x11
GS rims and 315/35 Kumho's up front so the front brakes are getting a work out. FYI I bought the Wilwood 6 piston kit from DRM first and found you have to space the wheel out 3/4" to get them to fit or you need custom rims. The 3 outboard pistons make the caliper pretty thick. I also remember if you bring the rotor inboard any further it hits the steering knuckle. I returned the Wilwood kit and got the C5 kit instead. FWIW.

Larry :seeya :hurray: :steering: :yawn: ;)

 

Thanks 4 the input. And welcome 2 the Forum.


[Modified by edsalinas, 9:01 PM 6/19/2003]

 

I'm working on a kit myself using the Billet 6-Piston Wilwood calipers and my own CNC Billet Brackets and Hats with 13.1" 1.25w rotors that will not space the wheels out at all...I should have my 1st kit finished in another 3-4 weeks and I'll post some pics up.

 

Once more guys! I have allready 13" Grand Sport brakes. But ican i use 14" disc with same thickness and stock GS caliber? Plese do understand at i dont need C5 brakes! :cheers:

 

:hurray: :hurray: :hurray: