99Lingenfelter

Took my car in to be dyno tuned after my FAST swap. (Mamo FAST 102, LS2 TB, 100mm MAF, LS3 injectors). With the new MAF and Injector tables loaded, the car runs out of fuel at 5500RPM. Fuel pressure is 60psi at 3500, 55psi at 4500, 45psi and falling like a rock at 5500. Looks like my factory fuel pump just can't keep up.
So, what do you guys recommend. Should I install a Walbro 255lph in tank pump, or add a boost a pump? Thoughts?

White Out

Go with a bigger pump over BAP. It's a cleaner install, no worry about a secondary system failing or prematurely killing the pump, and a Walbro 255 is cheap.

The Walbro 400 is a good option too.

99Lingenfelter

Sounds like at this level an in tank pump would be the best. Any idea what kind of rwhp the 255lph can support? I've read that its actually 225lph with the stock wiring.

martysauto

How much rwhp should you put down? How many miles on the stock pump and filter? To be safe, I suggest adding a hot wire kit when you install the new in tank pump. Your stock pump may be on its way out. Adding a BAP will just finish it off.
I think the stock fuel system can easily handle 450rwhp.

Sigforty

Not sure what power level you are at, but the Racetronix pump and wiring harness is capable of supporting 600 rwhp. I put that in my Z06 back when I did the stroker engine.

99Lingenfelter

Not sure what my rwhp is yet but my guess is between 450-475 on this dyno (really conservative). Car ran out of fuel pressure on the dyno. It was at 405rwhp at 5500rpm (Dyno Dynamics dyno) when the fuel pressure plummeted. Factory fuel system had 48k miles on it. I'd be surprised if the pump was getting weak with that little mileage but it is possible.

Car is a 383ci, small cam, ported ls1 heads, fast 102. Sounds like a 255lph pump with the racetronix wiring would be sufficient for the motor itself, but will it leave me much room for future mods? Would it support a little nitrous? I would like to be able to add a 125-150hp wet shot.

Sigforty

I have a 383 making just over 500 rwhp NA and I ran a 200 dry shot with the racetronix system. I do not think you will have any issues. Once you get over that 150 though you probably will want a stand alone fuel cell for the nitrous.

I am currently running a direct port, and never chanced my regular fuel system with it. I went straight with the stand alone.

99Lingenfelter

I don't plan on spraying that very often. I'd really like to install a regular system capable of supporting my NA power along with a future wet kit. I hate doing things more than once, and would like to avoid the stand alone system if possible.

StatmanRN

I have run the BAP with a stock pump and custom wiring. No issues at 534HP and 10#, but prob at the limit.
THe BAP can be wired to only kick in under load.
I have run various voltage boosters to electric pumps for years. Others say they have had problems
A pump is probable cheaper if you can do it yourself Though, and will be all you need for a while