[Sam335iE92]

Hi,

I am new too the forum so excuse my ignorance on some things here!

I have a 335i AT with full bolt ons. I’m running MHD stage 2+ E30 and XHP stage 3 on the gear box. I have a bigger front mount cooler, dual cone intakes, catless down pipes, alloy boost pipe, index 12 injectors, R8 coil packs and the PE or M3 mod on muffler. I am yet too change the plugs, silly I know.

The car goes in shortly for a new lpfp and flex fuel so I can run e50. I did some logs today on MHD V10 e30 and the lpfp is still producing around 70psi pressure on WOT 3rd gear. And it seems very stable. Considering when I bought the car it had index 12 injectors and dual cone ínstales but no tune, is there a change maybe the lpfp has been upgraded also?

Thanks

[dmckmc]

my fuel system is stock and i can push the ethanol to the mid 40% range. When I reach 50% or more ethanol, the stock lpfp cannot keep up and misfires on WOT. you could try pushing the ethanol and monitoring performance and pressure readings to check or look at the pump itself. Pump is easy access under rear seat.

[Sam335iE92]

Originally Posted by dmckmc

my fuel system is stock and i can push the ethanol to the mid 40% range. When I reach 50% or more ethanol, the stock lpfp cannot keep up and misfires on WOT. you could try pushing the ethanol and monitoring performance and pressure readings to check or look at the pump itself. Pump is easy access under rear seat.

Thanks, sounds like the simple option is too just check the pump out! It goes into the shot shortly anyways to have the pump replaced so I’ll just do a quick check before that. Thanks

[lookalikehuuh]

I found my OE fuel pump could support around E38ish before it would have issues with flow some time ago. Below the E38ish mark it was rock solid at 70-75psi.

I now run E50 mix year round and my Walbro 450 does great (VPN-F90000267 model).

Just FYI, you will see pretty significant pressure variation once you go with a high flow fuel pump since the EKPM (fuel pump computer/module essentially) isn't calibrated for it and is having to constantly adjust current.

Also super important, you EKPM will likely overheat like mine and many other here have experienced. Look for threads where we installed cooling solutions for our EKPMs. There is a lot of mixed data on whether EKPM2 or EKPM3 are better but for me they both had the same warning so they just aren't designed for that type of current IMHO.

The error I experienced had to do with excessive current for the fuel pump or something like that and would cause the car to go into limp mode.

Here is one of the threads: https://www.e90post.com/forums/showthread.php?t=1737938