Old PBR corvette rotor brake setup.

[Toul]

So I have a 93 with machined Gen 1 knuckles, the rotor that grinds on the LCA , and a 12.5 rotor.

I'm swapping in 94 knuckles from my parts car, and going to a 13 inch rotor.

I thought that my brake setup used the same caliper bracket and caliper as the cobra brakes, so I had assumed that the swap to 13 inch rotors was only going to require the rotors and the 94/95 knuckles.

That does not seem to be the case.

My brackets don't lineup with the tabs on the knuckle, so it looks like these aren't cobra brackets? What did these brackets come from?

Will the calipers I currently have fit into the cobra brackets? The manner in which the calipers fit into the brackets looks the same.

Also, hey, I haven't posted in quite a while.

 

[St Louis SHO]

If you buy cobra brackets, everything else will work.

 

[Toul]

I sure hope they fit under my 16'' rims.

 

[St Louis SHO]

They will...

 

[Toul]

Oh I know. I'm gloating. Thanks for the wheels.

 

[rbruso]

Unfortunately, Cobra brackets are about $85 apiece. Price has gone up a bit.

F4ZZ-2B292-A
F4ZZ-2B293-A

 

[Toul]

Ouch, especially after dropping coin on air compressor, end links, tie rod ends, rotors...

See if I can't find them at a junk yard.

 

[Shoaz]

I sure hope they fit under my 16'' rims.

You cannot count on 16" rims fitting over the 13" rotors. Slicers will not, many other won't, I'm not aware of many that do. A mockup before final assembly may be worthwhile.

 

[Toul]

http://www.shoforum.com/showthread.php?t=65399

I'm too lazy to make my own mockup.

 

[gmorrell]

Never mind...

 

[K-Dawg]

With the lower hat offset of the 13" Cobra rotor, the caliper moves outboard, and clearance to the wheel spokes can become an issue, even if the wheel diameter is large enough to clear the radius of the caliper. It's a rare wheel indeed that can fit over a 13" rotor and caliper.

I don't know your end goals, but perhaps beyond satisfying some rotor-envy issues, changing from 12.5" to 13" rotors is probably not going to make a huge difference in the car's braking capabilities, unless you're into hard-core open tracking. It will increase front brake torque, and unless you do something to pull the system bias back rearward a bit, the end result of all your hard work may be to enable more spectacular hand-stands.

It's your car, your effort, and your money, do as you please, but this seems to me like a lot of effort for little benefit.

Cheers.

Most 17" wheels will fit over the 13" PBR Cobra brakes.

The benefits I see of the Cobra setup are cheaper rotors and rotors that don't cook/grind your lower ball-joints. And it'll be easier to upgrade to a Gen 3 subframe if desired.

 

[Toul]

Thats exactly my line of thinking, cheap and easy to replace a rotor, and I don't have to grind my friggin ball joints.

As far as end goals, I plan to do the 11.6 upgrade out back eventually, but that will wait till I'm in there upgrading control arms.

Also, I realize that the transition from 12.5 to 13 rotor would not make much difference, but add in new tie rod ends, end links, lca's, and some EBC yellow pads instead of econobrand, and I think I should see a noticeable difference, worthy of my effort.

 

[St Louis SHO]

Do you people realize he has TD PR2 in 16" ?

 

[32MTX]

doesn't one of the TD's clear 13" cobras on 16" wheels....

 

[St Louis SHO]

:facedesk:

 

[K-Dawg]

Do you people realize he has TD PR2 in 16" ?

I gathered that.

 

[32MTX]

 

[Bob Gervais]

:facedesk:

So much for checking links and being an informed poster, eh?

 

[zak]

:facedesk:

Desk jobs are getting more dangerous all the time.

 

[Toul]

Looks like the caliper brackets that the corvette rotor used is just the normal cobra bracket, but the tabs that stick out to run the bracket bolts through are cut off flat, with new holes re-drilled to allow for the use of the custom bracket.