How much horsepower can a tbi setup with a 670 holley throttle body, on a carb intake support? I was planning on using a 16197427 pcm with the maf conversion.

 

i have heard that only 275 fwhp. im sure that it can support more than that but i cant prove it. my guess is around 350 fwhp with the psi at 25.

 

285 FWHP is the specification from Holley. The stock type GM injectors can push more fuel than the Holley injectors. Running on a BBC TBI, it can make more power than the Holley, over 450 FWHP is possible with a single 2bbl TBI unit.

 

I can say personally that a stock throttle body and injectors will support 300+hp. My current combo makes 300 crank hp and that is with a stock but ultimate modded throttle body and 61lbs inj at 20psi. Pretty sure I still have a little room to spare.

 

is it possible to use the injector from the stock tbi (350 injectors)on top of the holley tbi?

 

well what about with the 454 injectors? Is the limitation air flow, or fuel flow?

 

The GM injector pod can be made to work with the holley throttle body base, but it takes a little work. Read through the tbi stickies. There is a bunch of information on what is needed for higher power levels.