Scott Coyle-What brakes....

[Clois Harlan]

Hi Scott,

I enjoyed your Road America video and remember watching you on a couple laps from my cockpit. From my perspective at the track your car seemed to be braking fine but I guess only you can know how well they are working.

What front brake set up were you running at Road America? What setup are you planning on changing to? Also, you mentioned your car was "hunting" a little at speed (mine too), I don't remember if you had a front spoiler or not on your car.

Anyone here running a front spoiler that has ran their car without one?

Thanks,

Clois

[coyled]

Clois, I was running willwood 1 3/4 four piston calipers on 12.2 rotors in front and single piston pbr's in back on 12.2 rotors. The rears were smoking and the peddle was sponge at Road America. I have since changed to 4 piston 1 3/8 calipers in back. We'll see how it works. The cobra was stable at speed but the front end would wiggle when I went to the brakes. It only does this at very high speeds, say above 140mph, going into turns 1, 5, and canada corner. I am running 3 1/2 inches at the frame in front, that might help. Scott

[RACER X #99]

Scott,
My car was doing that wiggle the first time out ot the Glen last year. 150 on the front straight and I went hard on the brakes and was all over the track. I had way too much rear bias cranked in. I kept backing off on the rear bias and after a while it stopped being so squirrely. Probably going for the six piston superlights this year.

RD

[coyled]

Roger, What brakes are you running in the front and rear? My wiggle is in the front. The back feels stable to me. Scott

[RACER X #99]

Scott,
Right now four piston Superlights up front with 12.19 rotors. Out back 4 piston Dynalights with stock Jag solid rotors. Performance friction 93's all around. These brakes are OK but I want to go deeper and really scare the crap out of myself.

Roger

[coyled]

Roger, I have been thinking about the 6 piston willwood gn caliper in the front. They will work with the 15 inch pin drive hubs I am running. But, one change at a time. You going to make it to Road America next year? Scott

[RACER X #99]

Scott, Most of the guys in Club cranky have really enjoyed your video and are anxious to drive the RA track. I can't say yes for sure but it is a strong possibility.

BTW the six piston I am considering are the new Superlight six piston caliper. Same mount as the standard Superlight.
Roger

[Greg Kulp]

Forgive this supid question... I've seen it debated elsewhere. How do you count the pistons on brake calipers? Is it the number of pistons on one side of the caliper, or is it the total number of pistons on both sides? When you say 4 piston, is that 4 on one side or 2 on each side? Does that make any sense?

Thanks.

[RACER X #99]

Greg,
Total of both sides.

[a427sc]

Scott, is it a back and forth wiggle, or does it seem to dive/drift to one side or the other, not necessarily consistantly? When your rear brakes give up, the bias goes to the front, and makes the front "hunt". If it seems to be a little darty or drift one way or the other, it could be flex in the wheel bearings, the hub or the rotor hat. Solid mount calipers with rotors that flex around will give you pad knockback, and inconsistant braking force. Some times g force will help slide the pistons back if you don't have some type of residual valve either in line or in the master cylinder. AP has some info on rotor mountings and hat design, including floating mounts in the rotor or in the hat to compensate for movement. I think you have about the right sizing for the new calipers, but I never thought much of the old style Wilwoods after I tried the AP's. You should also look into diferential piston sizing if you are going to get new fronts.

Don

edit: Just saw all the info on shocks and spring rates from Morris and Dr H. on the other thread. Forget what I wrote above, and follow their leads. They forget more every morning than I will ever know.

[Greg Kulp]

Thanks Cranky. Makes the most sense to me.

[coyled]

Don, watch the video. Its a wiggle both ways not just hunting one way or drifting. You can see it going into turn 5. Scott

[a427sc]

I got a little tiny monitor and bad eyes. I find it hard to get a full sense of the problem. Of course, if you want to meet me at a warm weather track out your way and let me get some seat time, I bet I could get a better sense of it .

Don