Thread: AutoX brake setup

If you go with AD22VFs, get the NX2000 master cylinder. The front brake bias increases if you keep the Sentra MC, which makes the car more difficult to drive quickly in the cut/thrust autocross environment.

This is the 10th year I've been autocrossing my SE-R on a variety of pads and tires, but the first on AD22VFs. I have Carbotech Bobcat pads and the stock MC, and dislike the setup, no fault of the pads. I could probably be quicker on the stock AD18s. Because of stock MC bore size, you wind up with a firmer pedal and less pedal travel. Throw in the additional front bias and increased swept area, and you get more front lockup that's more difficult to modulate.

In momentum areas, this is no big deal. In pin turns and the stop box past the finish, it turns into a pain to stop the car without lockup. I left-foot-brake like a natural and can threshold-brake a non-ABS car no problem, but my SE-R's next upgrade will be a NX2000 MC.

I don't think AD22VFs are necessary for autocross (even boosted street cars). Heat dissapation is a non-issue on a SCCA-legal course. Trackdays are a different story. On road courses, AD18's are useless, no matter what kind of nuclear-meltdown-proof race pads you run. For autocross only, AD18's are just fine (lighter, in fact). Just get good pads and run decent tires.

Agree with Jim. AX just never gets stock 18's hot enough to bring them to fade. I may be the only one here who's actually done the nx2k mc; it's not the mc but the BIAS VALVES that restore the bias to the rear. You don't get the nx2k bias valves when you buy a rebuild, in fact the part # is the same for both cars. Greg at G Spec can drum up the new nx2k mc; 'tis from him I got mine. Makes a BIG difference; with the B13 bias valves you're not getting much rear brake with AD22's up front.

wow great info Thanks man. I have been thinking about a AD22VF's for a long time now, but i see alot of people that are doing autoX are using slotted rotors. I know tires play a important role in this, but i kind of want to try my street tires 1st. I am running Kuhmo ASX atm. Power slot rotor /w hank pads, stainless steal lines. Also what tires should i get