W/A intercooler? Heat wouldnt be an issue any more than with any other FI car. It wouldnt be hotter because of a smaller throttle body. There would be a large pressure drop accross the throttle body at some point. I run a 90mm throttle body for better air distribution in the plenum, otherwise I'd still be running a 70mm throttle body.
I never had my truck on the dyno with the 76mm turbo, but it trapped 4mph faster than when it made 570, an that was only at 14psi. If I was running the same 17psi I was with the 64mm turbo it would have been MUCH higher. That was with a 65mm throttle body, a GT40 intake, and stock GT40 heads. I wasnt limited by anything other than the presssure I was running. Sure, it would have made a lot more with better parts, but I also could have made a lot more with what I had.