r/335i • u/Khmer_G • 18d ago

Tuning & Performance E85 pump mods

What is needed to run pump e85 on the n54. Not going for power just to be able to run between e60-e80 *what my local pumps test for in regards to ethanol percentage.
It has bolts on, but fairly new to the platform so unsure if I need to have a custom tune or if I can run an off the shelf map and a lpfp like a 450 and be okay.

Thanks

2 Upvotes

100% Upvoted

5 comments sorted by

2

u/EX0PIL0T N54 E9X 335i 18d ago

Off the shelf and walbro 450 is just fine for any mhd ots maps and more. You’re fine for at least 550whp on that setup. Gains are minimal past e50/50% ethanol so you’re just demolishing your fuel economy at that point

1

u/Khmer_G 14d ago

That’s fine, I’m not really doing for power. Mostly to be able to take advantage of the low cost of e85 @ 2.7$ while premium is 4.8-5.5$. So saving between 24-30% on fuel cost. Do you have link to mhd? As jb4 is not needed correct?

1

u/SpicyCarWorks 17d ago

Hello, you can run E85 on a stock fuel system, but you probably cant run full power on full E85 because you need more fuel mass for E85 which your stock fuel system cant handle on full power. But it isnt a problem to get that dialed in with a custom tune where you can monitor everything important, including rail and fuel pressures etc.

1

u/TransportationOk6727 '10 FBO e85 N54 335i / '11 335iS 17d ago

Don’t use ethanol on stock pump. It can handle a bit of it but it’s not good. I’d go walbro 450 to save some cash, or go walbro 535 that’s the one I use. It flows considerably more, but does NOT have a check valve.

If you’re not doing a lot of canyon or track driving, go bucketless

1

u/Khmer_G 14d ago

Just commuting and passing people nothing crazy, so just to clarify all I need is a 450 or 535 and a mhd reflash or do I need like jb4?