Rev limiter limits??
I have a large cam with built motor, too. If I want to take it to the limit, I shoot for between 6800 and 7000 RPMs. That allows for an occasional overshoot to around 7200.
DYNO it and see where it starts to put on brakes.
I guess after 6500 would be just a waste.
Good luck with the 7500 biggggggggg heads and bigggggggg cam maabe a FAST A/F management system


