n.m.racer

Anybody hear about these earlier corvette calipers on 93-02 F-bodys? I have heard about this swap earlier and im just curious about. Sounds weird but could be cool. Old vettes used 4-piston calipers on 12" rotors. seems like it could bolt up. If anyone knows anyone that has done this and has pics it be interesting to see them. Plus if anyone has any thoughts please chime in... especially if you have experience with those years of vettes.

76LS1BIRD

iTrader: (35)

I think you should stay this the C5/C6 calipers. Newer & better technology.

Wesmanw02

iTrader: (4)

You are referring to the old cast iron Corvette calipers used from 68-82...that would be more of a downgrade than an upgrade.

Although those calipers were considered state of the art at the time, they are basically paperweights now. Nobody wants cast iron calipers anymore (bad heatsoak, very heavy, corrosion issues) and I don't think they would stop your car any faster than your stock PBR brakes. If you've ever driven a C3 Corvette, you'd know those brakes look much better than they actually perform anyway.

The best upgrades these days are the C5/C6 upgrade (12.8" rotors, gravity cast 2-piston PBR calipers) or the Z06/CTS-V upgrade, with 14" rotors and either 4 piston CTS-V calipers or 6 piston Z06 calipers.

n.m.racer

well ive been looking into the calipers a lil more and have heard a lot of the common issues youre describing. Yes theyre heavy and yes the have corrosion issues. but when compaing cars and technology, ours should be a little better. Wheels, tires, and pads today have a way greater superiouty compared to the old stuff. but you guys are right, my original question asked about the calipers themselves, the gm ones at least, and youre right.

On the other hand, wilwood makes a replacement caliper for the 65-82 caliper. It is made of a lighter weight material, has stainless sleeves and pistons, and might be metric threaded to accept our stock lines. The caliper is the D8-4. If any of you like to look into i think its far greater than the stocker pbrs will ever compare to.

I am going to get ahold of wilwood and see if they get could the dimensions of their calipers. Theyre resonably priced, at about $250-$300 a caliper depending on the finish and where you get them. C5 calipers are about $150 new and the CTS-V is close to $200 loaded. I personally ran the C5 calipers on my stock 12" rotor and they sucked. If i went to a 13" rotor would it have been better... maybe but probably... but single sided calipers are not what I like. This caliper will give you the option to run your stock rotor and get rid of the weak calipers. Pistons are bigger in the D8-4 so your bite should definately increase and hopefully the spongy pedal. You guys should take a look at the caliper and see what you think. If everything alligns right this might be the best upgrade for your money. Since all other kits require rotors and/or adapter brackets "trackbrackets." Honestly if the caliper didnt have enough power and if it did bolt in place, you could use the trackbrackets and adapt the 12.8" rotor from the C5 onto it. Could be a killer set-up.

The link for the wilwood D8-4 is below:

http://www.wilwood.com/BrakeKitListF...ette&year=1982

Wesmanw02

iTrader: (4)

Perhaps something else was wrong then. I used stock F-body PBR calipers with stock pads for the first 2 years I owned my car, and they were more than adequate. More than anyone should need for typical street use. pedal was firm and the car stopped very well. The C5 calipers should be just as good or better than that. Nothing wrong with sliding calipers, but you're right, 4 pot fixed calipers are ideal.

I think with all the trouble you'd go through to adapt the C3 brake system (and judging by the price of the Wilwoods) you'd be much better off just upgrading to the CTS-V setup. You get 4 pot aluminum Brembos and 14" rotors, you can't ask for much more. I have them on my car and they are amazing, check out my writeup in this forum, it stickied at the top.

n.m.racer

Ive seen the write up youre talking about and I think it is really cool how you guys adapted those brakes onto our cars. Its like you bolted together your own kit. I definately think those brake will stop your car quick. Its really sweet looking

4pot is the only thing i will choose to upgrade too. When i say the pedal is spongy, I guess I exagerate a little bit. Ill say it isnt as firm as my dad's 06 colorado or 2001 impala. Ive tried to rebuild my brake system which I thought parts were bad, (booster, master cylinder, lines) and I never noticed drastic changes. Ive never got abs to kick on from the pure power of those calipers(which have been rebuilt twice). I just want a good upgrade to something I know I can get parts for 30 years from now( which is why I like your CTS-V Swap). I just run my 16's during winter with blizzak tires and I'd hate to due a brake swap for a simple wheel change.

SIK02SS

iTrader: (11)

PBR brakes are junk for track use. If you're just out to have fun they are fine. If you want real stopping and modulating brakes, skip them. If you're on a budget and after a good/cheap caliper, Wilwood SL6 Slim. They fit under stock 17s (and most aftermarkets), and are s much better caliper than the PBRs. Plus 6 piston calipers don't hurt. They aren't a StopTech or AP setup, but they do just fine.

I have stock calipers/rotors with Carbotech XP12 front and XP8 rear for pads with ATE fluid and I have had the ABS go haywire on track before. Plenty of stopping power from a stock setup.

Wilwood has a 4 piston (SL4) kit, but I am not sure how they will do on the front of an f-body. For a C5/C6 they are crap and are a rear only caliper

SIK02SS

iTrader: (11)

have you checked your pads? Are they glazed over? Is there any material left? Have you had the brakes bled and a good fluid ran through (Motul RBF, ATE, etc)

n.m.racer

Arent the rear rotors thinner than the 1.25" front rotors? Put yea, pads were new, werent glazed. theyre a semi-metallic pad but i forget the brand. They do all right. I just checked the pads last week and are still in good shape. I never had the chance friday to call wilwood but ill do it on monday. Cant find any dimensions on the stock calipers or brackets to compare but I can always go out and measure.

Foxxtron

iTrader: (1)

The rear rotor fiction area has a slightly lesser width (~1.022") as well as a lesser inner diameter. Therefore it's rotor has a lower MOI than the fronts, however the huge bias comes from it's stock rear piston size compared to the other hydraulics components within the system. Also, having a ~58%/42% factory weight distribution combined with a solid rear axle doesn't help this either. This is why no matter what aftermarket pad I've tried on the rear, the best of many was actually the GM factory pads, until I tried a decoupled torque arm (actually two, one global west and another that I engineered myself).

Also, bear in mind the total effective piston area is only effective on one side, regardless of single sided floating calipers vs. dual-sided "solid" calipers. Where the "stiffness" can occur is mostly due to applying the appropriate piston sizes with a solid caliper to make use of the hydraulic pressure over it's dual sides, but again the respective design invovled must carefully balance so the hydraulic system won't exert too much pressure over the pistons, which could lead to some serious disaster. The use of the material for the floating caliper is almost always one of a higher modulus of elasticity than most modern day "solid" calipers (e.g. ~ 30 million lambdas for most steels alloys used vs. ~9 to 13 million lambdas for most aluminium alloys, both @ ~ 400 Degrees F). This usually means slightly heavier weight and some slightly slower heat dissipation (since ferrous compounds actually absorb and retain heat more than their comparible aluminium counterparts), however proper bridge design can and will eliminate most, but never all of the floating caliper bridge flexing, nor can a solid caliper either.

Unless you're seeing brake temperatures over 1200 degrees F over a half-hour track duty with long straights leading into extremely tight turns, you're not going to benefit much with searching for a "solid" four piston caliper, except for a minimal and sometimes imperceptible "stiffer pedal", though I can say that there has been a history of QC issues with regards to the stock F-Body PBR calipers (the obvious poor upper bridge design doesn't help either). The majority of PBR's (sans C6 Z06) are actually quite well designed.

With all of that stated, the quest to upgrade the caliper will be moot unless the sprung mass is properly controlled as well as a good tyre compound. Even so, the pads as well as the fluid will make or break any disc brake system easily before the other obvious factors.