Owens: Body ridgity is optional for the NSX's.
But honestly, toyotsupra, does the list of allowed mods say that your car should stay at 600 pp?
It's getting pretty frustrating to answer all your questions. Everything you need to know is in the OP. Please, take 15 minutes and read thru it all.
FROM THE OP:
"Honda RAYBRING NSX (Honda TAKATA DOME NSX,
Honda ARTA NSX)
Engine stage 3
Optional: Ridgity Improvement
1100 kg
540 bhp
610 pp
PL: -
* bhp is not exactly the same for all NSX's. Make sure to stay at 610 pp
when aero is maxed out and everything will be fine. You may reduce your aero settings, but you can not make up for the pp lost by upgrading your engine (turn up the power limiter e.t.c.)."
If something is not clear, please ask.
Since you only get 530 hp, my guess is that your car is not fully broken in. Make sure to drive it in offline mode or in races online until you reach 540 bhp. You'll notice how the bhp increases from race to race up to a sertain mailage. When the bhp does'nt increase any more, do an oilchange and make sure to stay at 610 pp with aero settings at MAX.
NOTE: HP and BHP are not exactly the same. 610pp is what you should aim for. 👍