blkbrd69

First sessions with this car at Sebring. 4 - 30 minute sessions went through .230" of the Carbotech XP-12 one piece front pads or 1/2 the pad lining, even on all 4 pads? and only .019" on the rear Carbotech XP-10 one piece pads, barely burning the paint off the rear backing plates.

I did expect much more front wear, as my other C6 narrow body would use 2+ pairs of fronts for every set of rears, but this is 12 to 1?

Brake bias did seem very front heavy running in Competition mode, didnt rotate at all trail braking. Firm peddle but did get a bubble or 2 while bleeding rear post weekend, but didn't get any fade?

Can anything be done about brake bias? or is the Automatic Brake Proportioning system computer taking over anyway?

Set up;

C6 Z06, Carbotech one piece XP12 front XP10 rear.

NT-05 tires with way to many heat cycles.

Front Performance AFX HD 2 piece rotors using Coleman rings, stock rear rotors.

SS brake lines, Motul 600 fluid, Lambert comp. spindle ducts.

Chin Blue group 2:32 pace. By the way Chin blue is viciously fast vs. other intermediate solo groups i have ran with?

blkbrd69

Ideas anyone?

BEZ06

You say you we're running in Comp - were you getting much AH intervention??

Bob

blkbrd69

Very little. Active handling is not very intrusive at all in comp. mode, much less so than the same year 08 narrow body I just sold? About the only time it kicked in was about every 2nd or 3rd lap on the curb at turn 7 exit, and a few times at turn 1 transition bumps.

Car just felt like it had a ton of front brake dialed in, or rear brake dialed out the whole day.

Have sprint car seat time so am very comfortable rotating.

Last C5

It doesn't sound that far out of line. I'm a C5Z with a similar set up running XP10 front and back and that's about what I would expect to see. Somewhere in the 10 to 1 or 12 to 1 ratio. I'm a little surprised that your XP 12s are doing that well. You're not an ex-Miata racer are you? I think those guys take the rotors and calipers off their cars to lighten them.

theseal

my experience with c6z vses/drp/edc/abs and basic hydraulic bias is that the factory hydraulics and programming render the rear brakes to be for show only.

If you do the math, the hydrualics supposedly work out to be 65% front, which is probably not too far out of line, but in practice, the programming never lets the rears do anywhere near that much work.

BEZ06

Here's a rear rotor on my C6 Z06:




That crack doesn't come from the brake not doing any work!! It appeared after 3 days of hard running on the Rolex course at Daytona in Dec. I had to swap out a front rotor at the end of the second day because it cracked.

I go through probably 8 front rotors before wearing out a rear rotor, but they eventually do go - either crack or get too thin.

I'm driving this on the street right now, but my next event will be the NCM Sebring event the end of March - and I'll swap on a new set of rears before that event.

Bob

BEZ06

Here are some pictures from Sebring:













And take a look at cb63's great pictures from the Rolex 24 at Daytona recently:

http://forums.corvetteforum.com/auto...m-daytona.html


Scroll down and look at the rotors - a number of the cars have the fronts glowing pretty good, but if the rears are glowing they're nowhere near like the fronts.

The fronts just simply do a lot more work than the rears.

If you're straight line braking it will probably be hard to tell anything about the front/rear bias.

If you think there's a bias problem while trail braking after turn in, you may very well have a different problem, such as an alignment problem, weight distribution problem, tire pressure wrong, wrong size tire, wrong stabilizer bar settings, wrong shock settings (if you're running some kind of adjustable coil overs), etc., that is making the front end plow, which might be interpreted as the brakes being over-biased to the front.

Before complaining about the brake bias, there are a lot of other things I'd work on to correct a turn-in problem.

Just MHO!!

Bob