Gaffer

Driving in Germany yesterday, I was following a Merc driving between 130 and 150 on the de-restricted bits, but when slowing from this speed to 80-90 for areas with 120kph limits or for traffic, I heard/felt a vibration from the rear brakes as if the discs were grooved. The problem appeared to be heat related as the first application after a slowish section didn't generate the problem, but would re-occur after a couple of wind downs from high speed.
The retardation didn't feel any different than normal, and certainly didn't feel like fade, so the question is what was happening?

The condition didn't happen the last time I drove in Germany so may be pad thickeness related.

The car is a my99 UK 5dr with 20K and standard brakes.

Any ideas?

Cheers

Gaffer

Blow Dog

From my experience, braking from 145mph on standard brakes would practically kill the pads/rear discs. The rear discs are *tiny* as it is.

sunilp

but Cem youve never done 145

Blow Dog

No, youre right, I havent...but I have braked from 120mph and thats bad enough...

Gaffer

Thanks Cem, but what do you mean 'pratically kill' - surely a few stops from this sort of speed is within the design limits of the car? The braking was not excessive or panicked - just sufficient to alter speeds for the changing conditions.

Cheers

G

Blow Dog

It is only in the last couple of years that the impreza has stood out as a true drivers car so it wouldnt suprise me if brakes were a part many farmers didnt complain about.

I know that in my 2 pots in my MY97 car, the brakes would simply burn up on standard brakes. Have you seen the discs? They are pathetically small. The standard subaru pads arent that good at dispersing heat either.

I have uprated my pads and discs to group N spec and on an event like Donnington, I can expect serious brake fade after 2 laps.

The moment you hear that rubbing sound from the discs, depress if you can. That way, you avoid any chance of warping the discs (more so if you then sit on the brake pedal after a massive stop).

Trust me, when I say that the standard Impreza brakes are crap, they really are. They are on par with perhaps a mass market car such as a Ford Focus, maybe worse .
cem