Does anyone know what the stock fuel pump flow rating is? is it 140lph?

I want to upgrade my fuel pump to resolve my lean issue with my stillen SC but I don't want to go with something so large that it would over power my fuel pressure regulator and run really rich when not in boost.

I know that there are some people that are using the walbro 255 with their stock injectors without a return system, but I'm not sure how well that set up is working for them. I have searched and searched both this board and the others and can't find a whole lot of data.

I am thinking that the walbro 190lph would probably be the best bet, but data from others who have already tried either one would help.

Thanks...

 

+1
kinda in the same situation.........have headers, 1/2" plenum spacer, ztube, kn filter and was running a little lean from last dyno ....

 

If you dont have FI kit . There is no need to upgrade the fuel pump . A ECU flash can solve the lean condition for you . You may have to send it back and forth several times to get it good though

 

sorry forgot to add that i've since installed a 50hp dry shot nitrous......
also read somewhere that once you got wot, the fuel/air maps changes accordingly, ie..more fuel added to compensate?

 

Did you ever change your fuel pump? was it needed?

 

I dont know about the fuel pump sorry, but I would imagine that the UTEC ECU would be something worth considering instead (or an ECU reflash), allowing you to fine tune your fuel and ignition maps to optimize and protect your engine......

 

Ya man. I replaced it with a walbro 190lph. IT resolved my lean issue and gave me back some horses that i was missing. Car runs great now..

 

i'm no expert but i agree with Dartmouth above... just increasing the flow rate of your fuel pump isn't the best way to correct a lean condition (although i'm sure it works to a degree). the better way would be to tell the injectors that they need to spray more fuel (versus forcing them to do so via higher pressure) using either an ECU reflash or a piggyback unit (GReddy eManage Ultimate or TurboXS UTEC). that way you can fine tune your fuel and timing maps for optimal and safe results based on your mods.

 

Not if your stock fuel pump was loosing pressure....Even a replacement OEM pump resolved the problem, the walbro was cheaper and has a more flow capacity.