There are no performance enhancements on any countries RX-8. Remember the whole overrated horsepower fiasco? Well, the guys at M2 Performance in Concord helped develop the engine (as much as everyone creams over JDM stuff, with a few exceptions, the best RX-7 tuners/designers are in the U.S.) and he was saying that thing is being pushed to the max, when you consider streetability, drivability, emissions, gas mileage, and warrenty considerations. Also, the way Mazda designed the Renesis, it is VERY difficult to increase performance using FI, hence the slow availability of any aftermarket FI systems. Allegedly, Mazda is going to unveil an electronically assisted supercharger this year or early next year to boost somewhat anemic performance. But be prepared to watch reliability and reputation plummet alike when Mazda "certified" mechanics begin working on them. That's what eventually killed the 3rd Gen in the U.S. . . .dealers had NO CLUE and actually did more damage to somewhat unreliable cars that needed constant service. Ask almost any 3rd Gen owner, with few exceptions, we all have horror stories of paying dealers a small fortune to wreck you car further (mine was at least 5k and almost a blown engine when all I needed was a new oil pan gasket and some new vaccum tubing.
Anyway, my $0.02
chris
-93 RX-7 R1 CYM
-04 Infiniti G35c