I strongly recommend against Race Modifying the Acura NSX '91. Huge disappointment. I guess I did it in hopes that it would be as quick as some of the 3rd party race modded NSXs that I've driven in GT4. I'm hugely disappointed.
Max HP is 414 on only normal aspiration (no option for turbo or supercharger) with all upgrades. Final weight is 1045kg. I entered the Extreme Series MR race and won, only because the off-the-line speed was great, and it's handling is superb. On straightaways though, I was being passed every time by the enzo and '67 Lambo. Okay, not passed (as I blocked them), but was getting bumped into.
I must admit, for a short course, the car is superb, as it ducks and weaves into and out of corners beautifully even though I'm a mediocre driver, but on any course with a straightaway, such as Circuit de Sarthe (with chicanes), you'll be passed by supercars (200+) and above.
Not worth the $300k, and I feel like a dolt when I could have used that money for the subaru already race modded... Oh well. Time for some B-spec griding!