cuatrokoop

you had posted somewhere on here that you rewired a fuel pump for 14vdc instead of 11-12vdc...just wondering what all is involved in doing that, as i want to get more from the pump in the CQ, evenutally (its rated 11-14vdc)...

TIA...

MikTip

<center><img src="http://pictureposter.audiworld.com/6607/adjfpreg.jpg"></center><p>This was done on a "turbo" engine machine.

Its done to give a few more psi out of the pump.

"Only" required after install of larger injectors and with a "rising rate fuel pressure regulator".

Most Audi fuel pumps put out 70-90psi. Your fuel system only "needs" 55psi(stock) as controled by the pressure reg.

Adjusting the fuel pressure reg often achieves the same results, as wiring for 14 volts. Or change fuel pumps to a turbo pump, which puts out over 100psi. But you'll need an adjustable fuel pressure reg,(pic) to gain from either mod. ;o)

MikTip

Re: 14V fuel pump

cuatrokoop

i'm planning on running larger injectors on a custom fuel rail, along with an adj. FPR. thats all gonna be done when i get the cams ground and installed (spring break?), all of which is in anticipation of a 2.6L 20v . head and im in question are already ported/port matched, and my car is an early header car...

somewhere around here i had all the pressures and flows figured out, but now can't find that piece of paper (for some reason, i didn't pop the data into Excel....).

question about the turbo pump, i'd probably have to go with an S2 pump, as it should also be in-tank like the CQ's (i only have the 'murican release of our family album installed, need to load das vaterland version...).

MikTip

Audi fuel pumps put out much more pressure than you'll ever fully use.

Even setting fuel pressure reg to just 3psi above stock, allows the injectors to pump much more fuel than needed.

Most Audi fuel pumps, "New" pump out over 90 psi.
Over time they degrade to below 70psi.

You may just need a new pump?

cuatrokoop

i may replace it when i do the build up, since its noisy (it always has been though).

so you don't think the stock 11vdc pump would have a problem with a 2.6L 20v given the proper FP and injectors? one less thing i'd have to do if thats the case...i just wanna get this dern thing built!!