DE Brake issues

[Alan Goettel]

I have questions on two brake issues. I have an 86 Carrara, (stock with Porterfield Pads). I am mid pack in intermediate run groups.

1) I often get a front brake vibration after the brakes get warmed up, but it seems to go away later as the brakes get hotter.

2) My rear pads wear faster than my fronts.

I have heard a couple of theories for each of these situations, and I am prepping for a 3 day event in 2 weeks. What are some suggestions?

Alan

[ttweed]

Originally posted by Alan Goettel
I have questions on two brake issues. I have an 86 Carrara, (stock with Porterfield Pads). I am mid pack in intermediate run groups.

1) I often get a front brake vibration after the brakes get warmed up, but it seems to go away later as the brakes get hotter.

2) My rear pads wear faster than my fronts.

I have heard a couple of theories for each of these situations, and I am prepping for a 3 day event in 2 weeks. What are some suggestions?

For #1, I would guess you are getting some kind of pad deposit on the rotors which is causing the vibration and that it somehow burns or melts off at higher temps? I have not used Porterfield pads, though, so I don't really know about their characteristics.

I have no idea about #2, as my front pads always wear faster due to the higher loads on them, but I have never owned a Carrera, and maybe the bias setup is different than on the early cars.

My suggestion is to check your pad depth after every session and bring an extra set of pads to the track which have already been bedded in so that you can swap them out if necessary. Otherwise, don't worry and have fun.

TT

[ChrisBennet]

With stock brakes and Pagid Orange pads I think my rear pads wore faster than my fronts until I got brake cooling ducts for the front. After that it went to 17 days front/14 days rear.
-Chris

[Jack Olsen]

Rotors could be warped. As their temp changes, the specific shape of the 'potato chip' effect will change. I don't know if that would contribute to reduced wear, though.

[mm86911]

Run cooling ducts front and rear and then evaluate.

[Bill Verburg]

Your rears will wear faster than the fronts if you remain in the regime of under 33bar of line pressure. The factory did that on purpose.

At a track you should be braking hard and be above the 33bar knee most of the time.

I suspect that most of the wear is from street driving and perhaps you may need to modify your braking style to use shorter but more aggressive braking zones.

Another possibility is to use an adjustable p/v w/ more aggressive knee settings.

A third and far more expensive option is an adjustable dual master cylinder set up as described in this thread The owner didn't identify what chassis he has but in retrospect it is likely that it is a Carrera as these models have by far the worst stock bias.