how you guys doing i have searched every where but maybe someone here is into it deeply. I have a jdm itr stock motor with i/h/e i was wondering at what rpm is it best to shift at so it wont lose power instead of taking it all the way to redline because i believe that it stock it doesn't have power all the way to 8500.

 

dyno your car and look at the chart, youll see where you start to lose some power

 

I've seen this discussed many times and if you truly want to maximize your acceleration potential you need shift well past the RPM where your engine makes peak HP. The actual shift point is determined by your transmission and the shape of the HP curve. For our engines (whose peak is almost symmetric) and transmissions I think it is best to shift about 700-900RPM past the HP peak.

If your peak is between 8000-8100RPM then your shift point will want to be around 8800-9000 RPM. Guess that's why the Mugen ECU has a raised redline of 9100!

Allot of people will tell you to shift at the peak... they are wrong.