Help with Brake Upgrade, Rear Vented rotors Options

[Racing916]

hello,

I am currently upgrading my 914-6 to vented rotors. My hope was to take a Front "M" caliper and mount it on the rear using the 911 (69-83 Rear) vented rotors. I mock fitted the caliper and rotor and it looks like I need to place a small spacer between the caliper and the mount on the rear trailing arm (not a problem) The issue is the 911 rotors get larger as you get closer to the brake surface and rub on the "M" Calipers. Has anyone else had this issue? I realize they are larger for the parking brake, is there a parking brake delete option? 914-6GT vented rotors, suppliers?

Thanks for any help, back to the drawing board!

Steve

[brant]

I've had vented rear rotors on a 914....
absolute waste of time
but the way to do it is to take a set of SC rotors, turn them down, and then vent the caliper...


when I built my 2nd 914 race car I left them off!
solid rear rotors are more than adequate!

have you ever overheated your rear brakes?
neither has anyone else...
absolutely unnecessary..

but hey if you want to waste 20lbs or rotational mass fine with me
makes it easier for me to pass you!

I'm at 1837lbs wet with an all metal -6 racer now...
not something you can achieve with vented rear rotors!
(I'll be taking another 20lbs off this winter, by changing out to a mag engine case)

b

[Racing916]

I've had vented rear rotors on a 914....
absolute waste of time
but the way to do it is to take a set of SC rotors, turn them down, and then vent the caliper...


when I built my 2nd 914 race car I left them off!
solid rear rotors are more than adequate!

have you ever overheated your rear brakes?
neither has anyone else...
absolutely unnecessary..

but hey if you want to waste 20lbs or rotational mass fine with me
makes it easier for me to pass you!

I'm at 1837lbs wet with an all metal -6 racer now...
not something you can achieve with vented rear rotors!
(I'll be taking another 20lbs off this winter, by changing out to a mag engine case)

b

Brant,

My car is pretty well gutted. The car probably weighs a little under 2000 lbs. I have a 2.7 six that has been heavily modified and at Watkins Glen on the high speed sections the car seems to not have enough brake to stop the car without braking earlier than some of the later cars without running into them. I have had somewhat of a mushy pedal, we have added cooling, bled the brakes a bunch, new master cylinder (19mm), changed the proportioning valve that we thought was the problem. We also have tried several different brake fluids (racing) and the problem seems to come back year after year. I pump the pedal on the straights to make sure something is there because in the past it wasn't. Also, i have put a temperature gauge on the front and rear rotors and the rears are much. much hotter than the front. I get that this could be because they were not vented like the front, but thought the upgrade to vented in the back and a bigger master cylinder, and rear piston might help the problem.

steve