Ok I have a 454 tbi i'm swapping on to my monte and i'm working on the fuel system. First off i'm wanting to use an external fuel pump because my car originally had a mechanical pump. I found that a pump from an 85 ford truck with mpi uses a nice external pump and comes with all the mounting brackets. It is rated for a max of 95 psi but as I understand it this shouldn't be a prob because the tbi reroutes the extra fuel back to the tank so the pressure will stay in the 15-20 range. Here is my question will this pump have enough volume to support 300-350 HP. Second I was looking through a hayes manual for an 89 chevy truck, yes I know their junk i bought it for the wiring diagram, and i found something that doesn't seem right. It says that the 454 tbi uses a special high output pump and it runs at 26-32 psi. Is this right? Does it mean the injectors will take a higher psi than other gm injectors? Thanks for your input any info will be greatly appreciated. :hail:

 

Since Mustangs change their pumps to the similar 255 ltr/hr that we do for over 300hp, I doubt the stock truck pump will do it either.

As far as I know, all the tbi systems run 9-13 psi stock but they all can run 26psi if needed but you would need a vacuum regulator or major chip tuning to prevent flooding the engine at idle. You didn't say if you were swapping the 454 TBI onto a small block or big block engine. With a small block you are going to still need a lot of chip tuning with 454 injectors and a 300hp + engine.

 

I use the Ford pump with a Holley 670 in my beast. It has the 330HP gm crate goes 10,000 puonds and uses more gas than any two Third Gens.
Works great...