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fuel pump question

Posted: Wed Jun 25, 2008 9:54 am
by 16bit
if I install a new higher capacity fuel pump will I need to get a new tune done?

Posted: Wed Jun 25, 2008 10:00 am
by kula
nope.
Your fuel pressure is regulated by the FPR, so it shouldnt really.

Posted: Wed Jun 25, 2008 10:03 am
by 16bit
brilliant

Posted: Wed Jun 25, 2008 10:05 am
by Garry
Unless your tune was limited by how much fuel you had available. With a higher capacity pump theoretically you could up your fuelling and run a higher tune.

Posted: Wed Jun 25, 2008 4:55 pm
by 16bit
don't think so but I am gearing up to have an e85 map done so I just wanted to check if it would effect my current map. thanks all.

Posted: Wed Jun 25, 2008 6:36 pm
by Fatty
the walbro pump has more fuel pressure, hence it will deliver more fuel (effectively it's the same as upgrading to bigger fuel injectors). so i would've thought a new tune would be needed? :?

whilst i see what kula is saying about the fpr.. i thought the fpr is expecting a certain pressure, you give it a higher pressure to start with and it will output a higher pressure as well.

i could be talking out of my ass, but i had a feeling it does effect the tune.

Posted: Wed Jun 25, 2008 11:03 pm
by Woo
The regulator will increase the volume of fuel flowing back to the tank in order to keep the pressure at it's factory preset level.

So the pressure doesn't get higher unless the regulator cant handle the increased flow. This sometimes happens if you put a 255 LPH pump in instead of a 190 LPH.

The increased flow has some benefits due to the fuel being kept cool rather than sitting in the rail getting hot.