jerrypeterson

Almost forgot.

You should strongly consider brake ducts now that you are starting to drive faster.

mikegarrison

It depends.

Sorry, that's the best answer any of us can give you. Just be careful with a new set of pads on the track the first time. Be alert for issues that might or might not develop when you get them really hot.

And choose your spots to push your brake performance. For instance, it would be much better to find you had serious "green fade" issues at T8 or T3A on PR than at T2. T8 or T3A you have runoff -- T2 you will be in the tirewall. If your new brakes suddenly seem to "go away", that's when you need to slow down, do a cooldown lap, and pull off the track. You will probably be able to see the gasses coming off them in the paddock.

TubeDriver

Good points raised in this thread!


I have a local road with little to no traffic at night which is were I bed my pads in.

I run a cadmium plated, cryo treated blank OEM rotor with OEM pads for street and autoX and use painted OEM blank rotors with track pads for the track.

Switching rotors and pads vs. just pads only add a couple minutes to the total switchover time.

You don't really need that little screw to hold the rotors on, the wheel/lugnuts dod pretty good job of holding thing together.

mikegarrison

Yeah, I took all those little screws out of there.

jerrypeterson

You'll kill your wheel studs if you don't use the screws. Even at specified torque for the lug nuts, the disc will slip under hard braking.

Ask me how I know.

mikegarrison

That just doesn't make sense. Those two little screws can't possibly be the load transfer mechanism for the entire braking load. That would be crazy. They would shear right off.

The lugs clamp the rotor between the wheel and the hub, and the metal-to-metal friction is where the load gets transfered. At least, that's the way it looks to me.

jerrypeterson

I couldn't agree more. That was my own justification for running without the screws in the first place. Sadly, the reality is a little different than I expected.

mikegarrison

The braking torque load goes from the ground, to the tire, to the wheel. No dispute, right?

It also goes from the rotor to the pad to the caliper to the flanges to the suspension.

So the only question left is how it goes from the rotor to the wheel. If those little screws were part of the path, it would have to go from the rotor to the hub through those screws, and then to the wheel via the studs. Call that path A.

Path B would be from the rotor to the studs directly, and then studs to the wheel.

Path C is direct friction from the rotor to the wheel.

Both B and A go through the studs, so if you had stud failure I can't see how a switch from A to B would make any difference. But I think path C is the actual load path anyway.

There is also a non-torque thrust load, which goes from the wheel to the wheel bearing to the suspension. I can't see how this load would be affected by those little screws either.