[Guest]

Many people have mentioned the juddering they get on an EVO 6 at high speed. BTR in Castleford (who prepare rally cars) told me why it does it.

Apparently, the hub to which the discs fit is very small in comparison to the size of the disc. If it's not mated really carefully to the hub, it goes out of alignment enough to wobble at speed. The size of the disc vs hub amplifies the judder.

Add to this the fact that EVO discs warp very easily and you can see what the problem is.

Apparently, they get 2 rallies out of a set of discs before they have to junk them. A reskim on a road car doesn't always fix the problem. He told me the alignment on the hub has to be correct within 1/10th of a mm or less! To set this can take an hour a wheel.

One of the manufacturers is making up some EVO discs to fix the warping problem. I'll let you all know when I know more.

 

[Guest]

Black Diamond are supposed to be releasing a cross drilled and grooved disc within the next week or so.

You can also purchase Group N standard discs, which look very similar to the standard discs, but are apparently significantly stronger, yet cost the same if not less than standard units

Try ABP Motorsport on 01270 567177

Alternatively I attended the track day at Cadwell on Friday, running standard discs and EBC redstuff. I have removed the fog lights and added some brake ducting which exits directly onto the caliper.

Despite some serious abuse, I did not manage to warp the discs (a first), although the new pads were down to 0.5mm at the end and barely got me hone. EBC will reback existing plates for about £65.00. Whislt they may not last very long, they are terrific and cost a lot less than standard discs! Again, try ABP Motorsport and no I don't work there!

Co-ord sport will also cross-drill standard discs at £36.00 a disc, excluding p and amp; p. An expensive solution?

Food for thought and hope this helps

Regards

J-P

 

[Guest]

The warping problems come from the fact that the pads are too hard.
Try softer pads (which of course will wear faster) which will preserve your discs.
As for the juddering, I've not experienced it yet. Guess I've got too many other problems on my Evo to have

Cheers

Tarik

 

[Guest]

J-P : I'll try the people you suggest for Red Stuff : EBC tell me they have none in stock until May, when they manufacture some more - any suggestions to tide-me-over ?? I think your ducting idea sounds good, and probably saved your discs at Cadwell.

Also Re: Black Diamond discs, if their ones for Cosworth are anything to go by - save your money. I always found the standard ford ones better at least they lasted about 12k miles.Still, its nice to know its not just Cosworths that suffer from poor brakes.