Are you using the OEM Brembo calipers David or aftermarket? I know there are some aftermarket calipers out there (primarily Wilwood) which offer good weights savings. Not unsprung weight savings, but weight savings on all for corners nevertheless.

 

Can you post pic's?

Do the RR's use an Al hat on a parking brake assy????

My buddy designed the PFC disks, they have a newer updated design, wonder if it will be released for the EVO aftermarket, uses significantly less hardware

Also, can you measure the thickness of the friction plates on the disk (I don't mean the overall thickness), inboard and outboard, I'm just curious on any geometry difference between the new disks compaired to PFC or other's that you guys carry.

Thanks,

 

Yes, using OEM Brembo's, I do not want to change the stock brake or size. Going with a lightweight drag brake is not at all interesting to me, trying to keep the car a real EVO.

Yes, the rear rotors us an aluminum hat on the parking brake assembly. No I can't post pics, they are on the car. I am not going to measure the thickness either, I feel that is probably information Giro doesn't want out there.

If you do a search for 'evolutionary' or find his post in this thread on page 1, he has done more testing and has posted pics and videos.

 

Alrighty I'll do that... I'm assuming these are more geared towards racing applications? Al hat on parking brakes don't mix well for burnishing....

I am also assuming that you guys haven't sold any of these yet to the public?
After the disks are released there is no secrets about measurements.

 

None have been sold to the public through us. You are correct, buy a set and have a good time taking all the measurements you want.

Yes, these are geared towards drag racing, autocross and street use, not for road racing.

Aluminum hat for the parking brake is an absolute NON issue.

 

Is there some data supporting this?

In my experience with parking brake testing, Al hat vs iron. The same assy can never achieve the same brake torque after burnishing on an Al hat vs Iron (dyno data). The friction usually gnarls on Al friction surface, and actual on vehicle test the car rolls down the 20% grade.

Of course, swap it on an Al hat the brake will still work, but I'm curious if it will hold on a 20% grade to pass FMVSS135 regulation. Tests like this which products can't pass regulation is the exact reason why PFC does not have a two piece Al RR street disk for the Evo, because of weight difference/demand for a two piece iron/iron was never made where for BMW's they are.

 

Weight off of the Calipers would be unsprung weight. . .

Tires, wheels, hubs, spindles, uprights, control arms - basically anything that moves up and down . . . . all are unsprung weight.

And the aluminum hats in the rear will NOT cause any issues unless you are maybe playing Ken Block Gymkhana Super Rally Driver and e-braking all over the place to get the wicked cool drifts for +100 style points. . .

If you use it when you are parked to hold the car in place - there should be no dramatic burnishing effect. . .

EVOlutionary

 

Sounds like David likes them for street and drag use. I LOVE them for autocross and street use. On the street you will not tell any difference between these and stock rotors unless you are doing the occasional highway pull or stoplight showdown. But on the autocross course (and drag strip) you will feel a difference. I can actually feel the lower rotating mass and less rotating inertia. At first on the autocross course I tended to lock the brakes up a bit more (no ABS) because of this, but after a couple runs that went away and everything seemed normal again (as my mind and foot adjusted). Just quicker accel and quicker decel. . .

If you are interested in these I would call Buschur and get on the list for the first batch!!

EVOlutionary

 

Thanks Evolutionary.

I spoke with Martin at Giro Disc yesterday. We will be doing a group buy on these in the very near future, working out some details right now.

Martin said he is suggesting these as drag/autocross rotors and NOT for street or road course use.

 

 

i know this is a super old thread but dave i just looked on ur site and cant find the rotors are they still available?

 

No, I can't get them any longer.

 

do you have any suggestions for replacment light weight rotors?

 

Not really, we were using the Baer Eradispeeds but they aren't being made any longer. Giro may still offer some, give Nick a call tomorrow at our shop, maybe we can get them.

 

This is a shame, does anyone know of any viable options in terms of lightweight stock replacement/dimension rotors for us evo 8/9 guys? There must be something out there.