It does max at 6500 HP wise but would need to go to 6800 or so to overlap the power band, so maybe 6800 to get past to my next shift. I am running a stick so i kinda am looking in that range. Valve train wise I am good to 7500 without float but no need to go that high so redline with my shift light is going to be set at 6800 and rev limiter set point 7000. As far as the 90mm throttle body it is a little shy for race but would be fine for street use. The manifold lower has plenty of meat and sopports more flow than a 90mm TB will sopport. The lower so happens to be right on the money with a 2.1/1.3 port to taper down at the adapter and head to a 2.1/1.2 port with matching. I actually have a lot of porting experience with carburation, but EFI requires more air to make power. A carbureted intake is tuned to keep velocity in the plenum by two things one is the size of the venturi of the carburetor two is plenum, port size to maintain a high velocity in the power band based on CID and RPM. Fuel injection works on the same princeable but uses a tapered intake to increase velocity with rpm based on runner length. Kinda a funnel effect, as velocity is only a concern at the injector point. This is why more air can be stuffed in a MPI system. If you chocke the intake at the throttle body or intake fresh air system it does squat and the whole thing runs like a dog after 4000 RPM. As far as the HP numbers the same engine on Barry,s site produced 650 HP with a caburator and a few less goodies. So I can expect a little better comfortably.
