I did a few searches and not much came up to give me the answers I seek.

The C4 rotor is 12". The PBR caliper is dual piston.

What are the specs on the LS1 caliper, and how does the C4 kit compare?

Where to obtain the C4 stuff, and what type of install is required? If I recall correctly the GM Performance catalogue, shows them for the LT1 f-body.

All information is appreciated.

Thanks in advance.

 

stock '88-'94 C4 brakes are 12"
J55 (heavy duty) option brakes are 13",
all ZR1 and '95-'96 brakes as 13". 13" setup is same basic design as 12", but thicker rotors, different mounting brackets, and wider calipers.
12" C4 brakes are easy to get used off corvetteforum.com, nobody wants them when they upgrade to J55. I believe the aftermarket units sold in various places are the 13" brakes.
'84-'87 are different and aren't the ones used in the kits.

 

Thanks... great info.

 

I have one of those calipers - fresh reman in a box, $50 + shipping gets it

 

Why a C4 kit and not a C5?

 

....because some of us are on a budget. 12" are still better than 10".

 

Pretty hard to beat my C5 deal.

I bought the Bob Bishop brackets for $150, then I bought a complete c5 brake setup...rotors, calipers, pads, brake lines for $125 used.

So for less than $300, I have a C5 setup.

The difficulty in repeating this now is that the Bob Bishop brackets or LG brackets are running almost double that even used. But the C5 stuff is cheap used from Corvettforum.com.

 

Sounds like you and I got similar deals. I've found a place (http://www.rockauto.com) that sells Raybestos C5 rotors for $18.42 a piece. Just got both of them via UPS a couple of days ago. They look great and some corvette forum guys are saying they're lasting better than GM rotors. I'm game to try them.

 

If you are referring to the 12” C4 front rotors, and the 10.9” LT1 front rotors, then I disagree with your opinion that “12 are still better than 10”. Those 12” C4 rotors are .8” thick. That is 4/5 of an inch. The LT1 rotors are 1.27” thick. They have much more internal vane area for heat dissipation, thicker cheeks (inner cheek .365”, outer cheek .320”), and more total mass. I used the original stock LT1 rotors for 4 years on street and track (with brake cooling ducting on track), and watched many C4 owners replace their rotors quickly. Usually after a couple of replacements, they upgraded to the Z51 C4 front brakes, which used a 13” x 1.1” rotor, which was better, but still cracked and warped faster than LT1 rotors. I don’t recall ever seeing a warped LT1 front rotor. All other things being equal, the larger the diameter of a rotor, the thicker it should be to minimize warping.

I don’t say IMHO because it should be obvious that this is my opinion, and I doubt that I am much humbler than the rest of you.

Bob Bishop

 

I had a '91 C4 with the 12" brakes I sold about 9 months ago. My non-technical opinion just based on changing pads/rotors on the C4 versus my '95 Z is that the rotors on the Z are much thicker & heavier, and the pads on the Z are much bigger as well. The rear brakes on the two cars appear to be exactly the same.

 

Mike,

Thanks for the lead on the inexpensive Raybestos rotors. Be sure to let us know how they last.

Bob

 

Thanks for the enlightening info Bob.

 

Thanks 94Bird.... I think I will order a set of those. That is pretty cheap.