Sorry for the response on a very old thread but with intake header exhaust, the computer doesn't correct itself so it would run lean like the Ap2's right?? So in that mind a FPR would be good by bumping up the fuel??

 

The stock engine management system will correct it's fuel trims in closed loop. Again, as it has been mention, the S2000 will err on the rich side of stoich. in open loop mode. With the marginal gains of a intake, header, exhaust you are not at risk of a dangerously lean condition.

 

I know a couple of people in a few different cars that have actually lost power (including myself but it was sponsored so it was ok ) with an adjustable aftermarket FPR over the stock one on an I/H/E/stage1-2 bolt on car.