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I am building up a stock NB for circuit racing. I have a few questions, I have already read the cams manual, I have a choice of original wheel size or 16x7 which wheel size is best on the NB?

Does anyone have feedback or advice.

AFAIK 16x7 wheels will allow you to run the larger NB8B/C brakes (appraently slightly larger than the NB8A rotors, but too big to fit under 15's)

Only problem with 16'sis limited tire choices. May come down to accepting the smaller rotors and 15's in light of cheaper, more readily available rubber, or slightly better braking performance but more expensive tires?

Depends on what sort of racing your going to do i guess..

if you have the budget the goodwin racing big brake kits are designed to fit under stock 15's. the latest version 4 use dba 5000 series rotors too. as for wheels pm me and I will send you an excel spreadsheet of a bunch of wheels and what they weigh. I would get the lightest that you can afford from this.

sirbob wrote:AFAIK 16x7 wheels will allow you to run the larger NB8B/C brakes (appraently slightly larger than the NB8A rotors, but too big to fit under 15's)

Only problem with 16'sis limited tire choices. May come down to accepting the smaller rotors and 15's in light of cheaper, more readily available rubber, or slightly better braking performance but more expensive tires?

Depends on what sort of racing your going to do i guess..

15" wheels fit over the NB8B/C brakes not problems - I use NB8A wheels on my NB8B for track work.

Also:

14" wheels fit on the NB8A but not the NB8B
16" wheels fit on the NC's.

casey, i beleive not ALL 15's will fit over the nb8b/c brakes. some do, some don't.

but yes 14's fit the nb8a brakes, thats the combo i use.

Fatty wrote:casey, i beleive not ALL 15's will fit over the nb8b/c brakes. some do, some don't.

Correct; 15" Starcorp Racing Lite fit over NB8B brakes; 15" Enkei RPF-1 do NOT fit over NB8B brakes.

You have to check before buying. I'd go with 15s though.

Boags

Really depends what spec. your race car is going to be...

If you are running 2F non turbo then 15x7 or 15 x8 are the best.

If you are running turbo and big horsepower generally you need to go to 16s or 17s...

Boyracer wrote:If you are running turbo and big horsepower generally you need to go to 16s or 17s...

Why do you say "need" there Lou?

Is a lower profile better for bigger power?

have a look at the 949racing.com 6ul wheels. they have a good range of 15's and are not too long of full race brake kit that is designed to fit under their wheels. the big brake kit will be using new willwood callipers too not the old dynalites.

Boags'MX5 wrote:

Boyracer wrote:If you are running turbo and big horsepower generally you need to go to 16s or 17s...

Why do you say "need" there Lou?

Is a lower profile better for bigger power?

2F's I think require the standard brake package on the car (Not %100 sure on this), if your running a faster 2B car your allowed brake upgrades and any of the big race brakes(AP/Brembo etc) won't fit under anything smaller than 16'. The dynalites are more of a street upgrade designed to fit under 15's I thought. The smaller Rotor/caliper would give you a much smaller surface area for heat disspiation and pad surface. I havn't read the regulations in a while though.....

Boags'MX5 wrote:

Boyracer wrote:If you are running turbo and big horsepower generally you need to go to 16s or 17s...

Why do you say "need" there Lou?

Is a lower profile better for bigger power?

Not so much about the profile of the tyre...more about the rolling diameter....the 15s just end up being too small and you run out of revs...

Ahh! Thanks guys. Makes sense.