I am getting ready to swap a 383 tpi into my 91 z. Hopefully about 400 hp.
I recently needed a fuel pump so I installed a Walbro 255 pump thinking that would work well with my new motor. It is so loud I can't stand it so it's coming out.
Heres my question:
What alternatives do I have for a stock type in tank pump? Researching on here I see mixed results on the noise level on Walbros. I am thinking I want to go back to the oem pump (AC Delco)....is there any reason this pump would not flow enough? Could I possibly use a 4th gen pump? (they support modified LS engines that are over 400 hp)

 

I can't even hear my Walbro 255 with my car running over my mild 350... I'm surprised you can hear yours, I only hear mine outside the car when it first primes. But you probably need the 255 to sustain adequate fuel pressure, the LS pump might work but I would stick with the Walbro since it is a drop in replacement.

 

Did you install the rubber isolation pads when you put it in? I have a 255lph pump and can barely hear it.

I'm not sure what a stock pump flows, but I don't think it would be enough for a 383. Might be wrong though.

 

The 4th gen pump ( just pump) is bigger then the tpi pumps. Physically. You could modify the hanger maybe. Trying to remember how the tube to the cartridge hat attaches. I know its heat shrinked on so you may not be able to attach it to the sending unit part.

 

ok. all of that helps... I wont switch to a 4th gen pump...didn't know it wasn't the same size. I think I must have gotten
a bad fuel pump out of the box..