Six piston caliper / 340mm+ BBK recommendations
 

Besides the Radi-Cal AP Racing kits (6 piston/355 and 372mm disks), are there any other kits with similar specs for the Gen2 cars? And do they require a BBK for the rear as well?

The Brembo GT Front 2-Piece Drilled Brake Kit 1M1.8047A1 comes with 6 piston calipers and 355mm rotors. Just need to know if I can keep the stock rears. The website where I found them doesn’t specify.

Lastly, do any of the 340mm+ kits fit 17x9 wheels?

I’d prefer not to have to buy new wheels and tires since I already have a nearly new set of 17x9 6UL wheels, but this is not a show stopper.

Brembo Pista, GT, GTS, GTR kits.

6UL will not clear any of the large kits. You will need 18" or very, very specific 17" wheels. Barrel clearance is a challenge when your BBK is serious.

I can get you set up with a complete solution.

The GRMN japanese 345 mm 6 pots brake kit fits under Rays ZE40 7.5x17 rims.

You do not need Uber huge brakes for the car. I read the other thread. I swapped to the Brembo BM4 from CSG and optionally the rear Brembo GT kit. You don’t need the rears but I prefer fixed calipers. Fits my 6UL, though I wouldn’t run those wheels on track. They are my beater street wheels and they are kinda ridiculous thin.

You’ll barely be exercising the BM4 kit. Don’t even bother thinking about ducts. See my build thread for more details.

Attachment 219588

Current street setup

Attachment 219589

I am considering the BM4 kit. And I’m running the 17x9 6UL wheels on track…six days so far. I ran them in a Miata (only 200-300lbs lighter) without issues. Have you heard of anyone having problems with them on track? I’ll upgrade/change them if so.

Did you do any track days with your stock brakes? If so, how did it go?

I threw some RS4s on and went on track with the stock brakes. Got 2-3 laps before significant fade. Upgraded to Carbotech XP-10 pads and race fluids while keeping all else the same. Got 4ish laps before significant fade.

A lot of people seem to do well with just better pads. I definitely did not.

I ran the Miata on stock brakes and $80 pads for over 15 track days without issues. I sold the car with more than half the pads still left. I’m not doing anything differently with the 86 in terms of warming up and cooling down.

In short, I think I’m just rougher on brakes than most people on track in the 86. The BM4 will probably be sufficient, but not too much. It might be better to go big big and never worry about it again. Don’t know ☹️

What tracks do you run at?

I didn’t run my car on stock brakes. BM4 before the event. Sadly I won’t get out til May8.

Just Summit and VIR these days. Usually with Trackdaze, Audi club, and maybe some private events.

That probably has a big impact.
I ran G-Loc R10 (same as Carbotech XP10) on stock calipers and ATE Typ 200 fluid at Mid Ohio (one main braking zone) and Pitt Race (three braking zones) without any issues.

I ran stock calipers/rotors with the XP-10s and ATE Typ 200 at Dominion which is much shorter and slower than Mid-Ohio and Pitt Race and overheated in about 4 laps. Did not have the issue in a Miata with stock brakes, $80 StopTech pads, and ATE Typ 200 fluid at the same track, but I was ~6 secs slower at that track.

I ran 6UL's for years, never had a problem with them. Early generations (1-3?) could crack but never heard of a gen 4 wheel cracking. Gen 4 has lug holes that line up symmetrically with the valve hole centerline.

That track doesn't look too brake heavy, but I'll defer to the more qualified experts. Did you have the chance to run other tracks with the same setup?

Exactly what I understood when I bought the 6ULs. And good experience with them so far.

It’s not a brake heavy track compared to VIR, PITT, etc.

Another thing that was not brought here yet - are you running with stability control fully off? Long press on the left button. Otherwise you'd get traction and stability actuation of the brakes that will quickly overheat them.

XP-10's aren't that great. I melted down a set even with BBK. I noticed they put a lot of heat into the rest of the system too.