Whats the biggest fuel pump that you can install ?? Walbro 340 255lph???
 

I need to upgrade the fuel pump on my 85. Im pushing 600 rwhp through the stock pump with an inline pump as a helper. its just not cutting it with more nitrous usage....

Alot of the ls1 f-body guys run Walbro 340 255/lph pumps. Does anyone know if this high pressure (60 psi) 255 lph pump will install straight in with no modifying? (i have an ls1 swap using stock lines etc so i need the higher pressure)

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (LS1Tuner)
 

Check http://www.racetronix.com.

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (LS1Tuner)
 

Pressure does NOT equal flow. A given size tube, will have a maximum volume capacity, beyond which, additional pressure will be meaninless. It sounds like you could use additional volume, not pressure. Good luck, and...

RACE ON!!!

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (CFI-EFI)
 

I wasnt implying the more flow from higher pressure.

LS1's run at 60 psi, most pumps put out 45 psi or so....i need the higher pressure setup

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (LS1Tuner)
 

Most pumps are regulated to 45 psi. You may wish to test yours to see if it will maintain the pressure you need. I'd like a nickel for every fuel pump that has been up graded, needlessly. Especially by the Crossfire guys. Good luck, and...

RACE ON!!!

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (LS1Tuner)
 

Yes the Walbro GSS 307 or 340 are drop-in replacements (the GM version comes with wiring harness adapter.) Physically they look exactly like the factory pump.

Keeping the voltage up is very important for flow/pressure; the factory wiring really sucks. You can get the Racetronix kit or just run some heavy wire from the batery accessory terminal thru a fuse thru a relay to the pump; use the original factory wire to switch the relay....

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (LS1Tuner)
 

Walbro does make a High Pressure pump that will flow at the high psi rate. It is still a 255lph. It was the one I got when I replaced mine. I'm not sure what the part number on it is, but if you IM me I should be able to look it up on my order slip in my files.

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (mn_vette)
 

My Walbro 340 says 80 PSI.and 255lph

Re: Whats the biggest fuel pump that you can install ?? Walbro 340 255lph??? (LS1Tuner)
 

Sounds like you may want to do more than just replace the pump.