Wilwood Rear Brakes

[stevenburgess]

Question, Does it matter if the Brake Caliper is on the top or the bottom, I have see it both ways?
Second, how close should the part that attaches to the axle be to the rotor, it looks like I need to add a shim. your thoughts.

Thank youIMG_2990.JPGIMG_2994.JPGIMG_2995.JPGIMG_2996.JPG

[Boydster]

I don't think it has much to do with cooling or debris protection, but more with anti-dive and anti squat. For most hi end performance cars, the rear calipers are on the front to use the braking force to help pull down the suspension, preventing the tail from going high. The front brakes are on the rear of the disc to prevent nose dive.

Of course, the whole reason for this is to prevent the CG shift, losing weight and traction in the rear and losing braking efficiency.

[2bking]

I don't think it has much to do with cooling or debris protection, but more with anti-dive and anti squat. For most hi end performance cars, the rear calipers are on the front to use the braking force to help pull down the suspension, preventing the tail from going high. The front brakes are on the rear of the disc to prevent nose dive.

Of course, the whole reason for this is to prevent the CG shift, loosing weight and traction in the rear and loosing braking efficiency.

Physics says the location of the caliper doesn't have anything to do with dive or squat. It's putting the same torque into the rear axle housing no matter where it is located. Dive and squat are the results of the axle housing attaching geometry. The preference for the location of the caliper would be for ease of plumbing brake lines, routing E-brake cables and access to the bleeder port.

[Boydster]

I cant find it now, but I recall reading an engineering paper on how the different caliper locations could unload or load the suspension. The amount of torque applied would not change, but where that torque was applied vs the location of the suspension, whether the applied torque was going towards the suspension or away from it. That kind of thing. I read it back when I was a big F1 fan. Then again, who says they are right? Thanks for the discussion.

[HCP 65 COUPE]

Boydster is correct in the anti squat anti dive Idea as the rotational inertia of the wheels and brake disk will impart a force into the caliper bracket when the brakes are applied, and either lift or drop the suspension depending on which direction the force is applied But I think he may have the directions flipped a rear mounted caliper would lift the suspension(compress the rear spring drooping the rear not allowing the spring to unload as easy) and a front mounted one would lower it(remove spring compression) so for anti dive it would be front mounted in the front of the car and rear mounted in the back. But don't take this for gospel make sure you check with a credible source as I'm no race car engineer.
Top or bottom mount should not change spring forces but just impart the forces into the suspension members at a right angle to the springs. Really all this only matters to the car on the race track anyways I don't think you would notice much difference on the street but I could be wrong, it will effect brake balance front to rear to a small degree.

[Oliver27]

Does Wilwood make rear brakes for the 15" wheels?

[chopthebass]

Does Wilwood make rear brakes for the 15" wheels?

I know Baer does. I have them fitted.

[stevenburgess]

What about the spacing between the rotor and the bracket that attaches to the axle. It is really close to the rotor. It does not touch but is close

[chopthebass]

What about the spacing between the rotor and the bracket that attaches to the axle. It is really close to the rotor. It does not touch but is close

Its very close, so I am using a 1/4" spacer.