In Defense of J55 Brakes

[bowtiguy]

Originally Posted by LGAFF

We put EBC red stuff pads on my wifes CLA45 it stops from 70 in 150ft stock, the pads have a lot more initial bite than the benz pads and zero dust

Benz pads Are HORRIBLE! Short life and high dust rate. I had hawk make me up a set of HPS pads for the wife?s AMG GL63. Better initial bite.....ZERO dust!

[LGAFF]

First drive:

• EBC Red Stuff Pads
• New Master Cylinder
• DRM Bias Spring

Initial bite is way better than stock, have to drive 200 miles before hard stops as the EBC pads use a break in compound. its 100% better than stock, Camaro master cylinder might make it about perfect from comments I have read

** I also changed my front coilovers to Aldan American from an old Carrera 525lb setup

[Erik]

Originally Posted by LGAFF

First drive:

• EBC Red Stuff Pads
• New Master Cylinder
• DRM Bias Spring

Initial bite is way better than stock, have to drive 200 miles before hard stops as the EBC pads use a break in compound. its 100% better than stock, Camaro master cylinder might make it about perfect from comments I have read

** I also changed my front coilovers to Aldan American from an old Carrera 525lb setup

Great update. Thanks!

Whats with this Camaro master cylinder thing?

[LGAFF]

4th Gen Camaro Master Cylinder has a much larger bore than the Corvette, supposedly it makes for a much firmer pedal feel.

requires some changes

[Matt B]

I recently installed my Powerstop Z26 package (all 4 corners) and can only say thanks for the advise. Whisper silent as indicated and good stopping power out of the box. Took her for a spin on the Autobahn last night with full confidence in my new brakes .

Let's see where they develop in terms of brake performance as I could not do much more as the break in procedure last night. And I hope that the low dust formula keeps its promise.

Anyway this seems like a good overall package. Thanks!20210728_080137.jpg

Sent from my SM-G991B using ZR-1 Net Registry mobile app

[Vette Guy]

I'm a huge fan of J55s. Reference my article in issue 56 of the HotB, found on the Registry website. If I could ever take someone for a ride in my 1988 Challenge Car, you'd be overly astonished - I outbrake many other race cars, including NASCARs and Lolas. That said, I rebuild the calipers / master cylinder each year, run DRM pistons, love DBA rotors and Carbotech XP-12 pads. I run through a set of pads each event, and get about 3 events from a set of rotors. I've never cooked my brakes, but have cooling ducts and run high-temp fluid.

I did purchase a set of Baer 4-piston calipers for my 1991 ZR-1 with the intent of comparing stopping distance between J55s and them, working out the change in rear bias to minimize braking distance... and at least providing members an upgrade recipe if they wanted - unfortunately, that project is on the back burner for a while.

My 96 runs runs Coleman Series IIIs with custom rotors up front, with J55s/13" rotors on the rear. It does not stop anywhere near as good as the Challenge Car, even with an adjustable bias bar and same compound. I plan to replace all the flexible lines and start over with the brake system (Tilton, triple cylinder - no booster, recirculating valve and rear pressure dampener).

I've seen lots of 6-piston conversions with stock rear calipers, and think this is a recipe for disaster on the track, such as Bob Saveland experienced on the dragstrip with this setup. (Issue 21, HotB).

Even taking front & rears from a newer Corvette and retrofitting them on the C4 isn't a good option without adjusting bias. The cars are very different.

That said, if your Z isn't track driven, 6-piston fronts and stock rears (heavy front bias) may not matter much, but know the stock setup will stop better.

Mark

[Karl]

The Grand Sport brake calipers are a step up from the J55 calipers.

https://www.corvetteactioncenter.com...rakes-640.html

A little beefier and thicker than the J55 calipers.

[Ccmano]

Originally Posted by Karl

The Grand Sport brake calipers are a step up from the J55 calipers.

https://www.corvetteactioncenter.com

A little beefier and thicker than the J55 calipers.

Agreed.... see page 1 of this thread.
H

[Norwegianmopar]

Originally Posted by Matt B

I recently installed my Powerstop Z26 package (all 4 corners) and can only say thanks for the advise. Whisper silent as indicated and good stopping power out of the box. Took her for a spin on the Autobahn last night with full confidence in my new brakes .

Let's see where they develop in terms of brake performance as I could not do much more as the break in procedure last night. And I hope that the low dust formula keeps its promise.

Anyway this seems like a good overall package. Thanks!Attachment 15908

Sent from my SM-G991B using ZR-1 Net Registry mobile app

Please update when you have tested them a bit more. I am going for Z26 too on our 94.

Sent from my SM-G955F using ZR-1 Net Registry mobile app

[Matt B]

Sorry, should have done this earlier. It's for sure an upgrade to the stock pads and rotors. No noises or vibrations (which I really appreciate), very little brake dust (well, actually it is not "little" at all but it's light grey so wheels do look better. However, it's no comparison to ATE Ceramic pads I use on my Audis which produce extremely little dust that's nearly invisible) and a solid brake performance.
Compared to modern road use standards I'd still say it's a spongy old brake that is hard to modulate and provides rather little feedback and feel. Though ultimate stopping power with Z26 in combination with my Michelin tires (275 & 335) is pretty impressive. When you hammer it, it hammers back. I'd definitely add some braided hoses for more feel