Replacing FAST EFI on HP 383, with what?

Space Duster, your over Analyzing the whole issue. That cam is also not too big for the heads you have. To be honest as a matter fact, it is a bit small, for the heads.

To effectively use what you have with minimal change, swap to a smaller cam.

TTI has headers that will fit. Schumacher creative services also has tri- Y headers that fit very well.

I don't mind swapping out cams, but what is the recommendation with the heads and rear end, the 750 cfm and assuming headers that many believe I need. Will I have to pull the engine to put the headers on and drop it all back in together? Had to do that with 2" headers on the '67 Satellite's 440. That's a big job for me with what I have to work with. I will definitely check with Schumacher and TTI. Thanks for the guidance.