The NA6 was not exactly blessed with large brakes from the factory. On my track car this had been previously dealt with by using integrated brake ducting which I installed by welding 3″ exhaust pipe onto the backing plate as a mounting flange, and then feeding some SCAT tube into the bumper opening. This worked well enough for the pace I was managing to achieve out of an NA6 with a stock motor.
The brake ducting worked well enough and for my purposes was significantly cheaper than a brake upgrade however after a while the NA6 stock calipers started leaking, the caliper pistons showed significant scoring so a rebuild wasn’t worth the effort.
The decision was made to move to the NB8B brakes, in Australia all NB8Bs came with the big brakes from factory, in North America these are referred to as “Sport suspension brakes” the calipers were sourced from rock auto. Second hand these brakes cost around $600 aud locally, or I could buy reman calipers from rock auto for approx $400 aud delivered. A no brainer, the stock master cylinder was retained during the upgrade.
This brake upgrade is a very significant size upgrade for NA6 owners, with the brake disk sizes below
Front disc Sport brakes = 270 mm
Rear disc Sport brakes = 276 mm
Front disc Non Sport brakes = 255 mm
Rear disc Non Sport brakes = 251 mm
NA 1.8 (1994-1997)
Front disc brakes = 255 mm
Rear disc brakes = 251 mm
NA 1.6 (1990-1993)
Front disc brakes = 235 mm
Rear disc brakes = 231 mm
The upgrade process is reasonably trivial, a little bit of trimming of the backing plate and they’re done. The only caveat is you need to make sure you source the caliper bracket with the caliper.
I am using Enkei RFP1 15×7 +30 wheels and they did foul on the caliper ever so slightly. Some people suggest that running 5mm spacers will fix this however I’m not a fan of spacers in general and I found that the outer casting marks on the caliper were only hitting ever so slightly on the inner barrel of the wheel, the wheel would mount and fit however you could hear the caliper dragging on the wheel. I was able to take an angle grinder to the casting dags and make enough clearance, for the wheel to spin freely, no more than 1mm of material was removed
Fitment on these enkei wheels is very tight, however they have an unusual step in the barrel you wouldn’t get with most wheels .
The brake bias has moved somewhat to the front, not an issue for street driving but it is noticeable on the track. A bias valve would be recommended but not strictly necessary.