M friend has a JRSC'd GSR running 8lbs. When he ordered a boost upgrade kit for the charger, it included a Walbro 255lph pump. Is this pump too big for his application? He has a fuel pressure gauge on his fuel filter and it shows a constant pressure of 50psi. I installed a B&M FPR and I couldn't change the pressure when either I loosened or tighted the spring. I think that this pump is far too big, but I'm looking for some other peoples opinions. Thanks for your input.

 

i dont think that its to big, you need allot of fuel pressure to feed the demands of the FMU, he is runing an FMU right?


Rob

 

Either way you can't have too big of pump. The FPR will sent everything that is needed right back to the tank. Sounds like there is a problem with the B&M FPR, the fuel pressure should start to change with the slightest adjustment.

 

he has the jackson FMU but he bought a cartech one that he should be putting on soon.

 

until the pump outflows the stock regulator...which will most likely happen.

 

you need to do the TOO bypass mod on the FPR with a 255 lph pump.

 

He doesn't have a stock FPR. If you have a stock FPR then you should be boosting and thus shouldn't need a bigger fuel pump at all.

 

ummmmmm....?

 

if you are upgrading the fuel system why even bother with the stock fpr? get a good one, a nice aftermarket unit will have different orifices {jets} that allow you to tune volume of returned fuel to help get everything setup {correct fuel pressure} they will also bleed down all your fuel pressure with the key is turned off. it does this to allow all the pressure in the rail to fall off, so instead of the pressurized fuel sitting in the rail getting all nice and hot from the engine {convection and conduction}. why is that good? well once you go to restart the car te pump will have to refill the lines, thereby p[ushing nice cool fuel into the rail instead of that heat soaked **** being fed into the motor. as we all know cool fuel = more hp

 

He was hitting 50psi at idle before we added the B&M unit and after as well, regardless of how much we played with the regulator. Something's just not right. We're going to try putting his stock pump back in and adding an inline pump and see what that does for us.