Thread: LPFP Tech info
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      12-26-2012, 01:08 AM   #14

Drives: X1, 335i
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Originally Posted by Zebra99 View Post
From all your info. I take that these vehicles don't consistently run the high pressure (72psi) on their fuel systems as we do. And that to me means more stress, more pressure and consistent running this means more wear. This the need for two pumps for support.....

Here is a stupid question....

Would it not be viable and easier to run a single pump system like the GTR's, Supra's and the like?

I know nothing about our fuel system other than the basics, but it just sounds like BMW made it extra complicated for no reason lol...has to be something to it tho.
Both the cars you mention run lower static pressures and do not have a crank driven HPFP at the last stage of the fuel system. So they aren't constrained by relatively high pressure requirements and pressure limitations in the fuel rail. Then again, they also don't enjoy the benefits of direct injection (knock resistance, off boost torque, lower emissions, etc). With the n54, being able to support up to 800whp (on gasoline) is pretty straightforward. Much above that and things will get trickier. Keep in mind that this is 300% over stock! With nothing more than an in-tank fuel pump add on. Most other vehicles would require injectors, fuel rails and a fuel pump to support that relative power gain. We really should be happy with what BMW gave us to work with.