ZR-1 Net Registry Forums - Brake Recommendations Please

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Re: Brake Recommendations Please

Quote:

Originally Posted by XfireZ51 (Post 226059)

Sam,

How does the difference in "swept area" play into this? You are looking at front/rear rotors that are 1" larger than the stock ZR-1 rotors. Again, I don't race the car, but my experience has been that the pressure needed to slow/stop the car is noticeably less than w the Brembos I had up front. I see that u have a 90 and it's my understanding that the master/booster for the 90 is smaller than what was used for subsequent years. Some have used Camaro master/booster for use w Wilwoods for example. In my 92, the master feels more than adequate in terms of pedal feel and travel in combination w the Z brakes.
Just to clarify for others following this thread, my beginning objective was to use the Z06 wheels for the aesthetics and tire availability. Originally the car came w Brembo fronts under A molds. When I switched to Z06 wheels, the front tires protruded past the front fender noticeably. Part of the issue was the extra thickness of the Brembo rotor hat. Swapping in the Z06 calipers allowed use of the Z06 rotors, which are heavier, but they also reduced the offset putting the outer edge of the front tire almost virtually in line with the edge of the front fender.
The 19s, on the other hand, made the 12" stock rotors and caliper look rather puny. I do use 18mm spacers on the rears for the proper wheel/fender alignment.

I suppose the Brembos didn't their work good because of not correct piston volumes. In my 1990 car I run a 6 piston Porsche brake with 330 x 34 mm rotors and sawblade rims and they do a good Job.
About 2 month ago I did install in a clients 1992 ZR-1 a Mov'it 6 Piston brake with 342 x 32 mm two piece rotors. It has now a hard pedal and the necessary pressure is low to stop the car fast.
The calipers work with different piston diameters. This combination provide a very fast braking reaction and a stable pedal pressure when you slow down from any speed. We did several stop tests from speeds of up to 280 km/h (like 175 miles) and the brakes had no fading and kept the car in line.

When you install in front and rear such brakes and slow down hard at high speed, it feels like somebody push the car down. It's a amazing feeling. A fit Mov'it outperform a Z06 or Wilwood or Bear brake.

The rotor offsets are calculated and designed for stock 9.5 x 17" rims with 56 mm offset. When you are going with bigger 18 or more inch rims you have to take that into your offset calculation. Otherwise the wheels can stand out of the car body.

Re: Brake Recommendations Please

I would think that '92+ cars would respond better to "bigger brake" packages because the pedal ratio was increased from 3.5 to 4.0 according to MVMA published specifications. The piston diameter of the master was also changed.

Adding the pedal and the pedal support from a '92+ car to a '90 or '91 isn't an issue (bolt on) but I'm not sure how the pedal push-rod is attached to the booster so whatever might be required there could be an issue.

I've not seen a '90/91 booster side by side with the '92+ either so is a modification to the push-rod to use possible?

If someone had access to some of the Corvette salvage yards they could likely do a "side by side" - to compare the push-rod length differences. It wouldn't need to be ZR-1 components TO COMPARE.

The correct ZR-1 push-rod was an available service part and the attaching to the booster I doubt changed.

Re: Brake Recommendations Please

WV,

Do you know if the pivot point changed from the 90-91 to 92+ on the brake pedal itself? I seem tot think that was something else too

Re: Brake Recommendations Please

Quote:

Originally Posted by -=Jeff=- (Post 226122)

WV,

Do you know if the pivot point changed from the 90-91 to 92+ on the brake pedal itself? I seem tot think that was something else too

You should need two pieces, the column support and the pedal for sure. Can the length of the push-rod be changed to accommodate? That's the only question I see. I've of course not done this but I've done similar changes when doing AT to MT swaps. The retention of the rod to the pedal is the same. The SLS bracket is the same '90 - '92 and was a bolt on. In '93 the SLS bracket changed but I can't see that being an issue.

Re: Brake Recommendations Please

Quote:

Originally Posted by -=Jeff=- (Post 226124)

SLS bracket?

Stop Light Switch

Re: Brake Recommendations Please

Quote:

Originally Posted by WVZR-1 (Post 226125)

Stop Light Switch

:cheers:

Re: Brake Recommendations Please

difficult to order/install? The website is tough to navigate and decipher for me.

Re: Brake Recommendations Please

Quote:

Originally Posted by TCurtner (Post 226132)

difficult to order/install? The website is tough to navigate and decipher for me.

Do you talk about the Mov'it webseite?

Re: Brake Recommendations Please

I want to keep my stock sawblades. What kind of caliper upgrades are there available? did the later 93-95 have bogger calipers? or could you guys recommend some brands/models? i do not want to change rims but on my next brake job i would like bigger calipers along witjh my pads. I like my sawblades too much to get larger wheels. In my opinion its the flagship rim of C4 and i love em.