[JaySingh124]

Looking to run e85 straight on my '24 m440xi. What upgrades are needed for this?

Also, the tank cover says up to E10 so I'm wondering if I even have the upgraded tu fuel pump to handle E30>

[RTPenland]

Originally Posted by JaySingh124

Looking to run e85 straight on my '24 m440xi. What upgrades are needed for this?

Also, the tank cover says up to E10 so I'm wondering if I even have the upgraded tu fuel pump to handle E30>

You simply need a flash that supports full E85, keep in mind the main reason to run full E85 on an otherwise stock B58TU is to save money at the pump, you will achieve optimal power on E30/E40.

[opium340]

Originally Posted by RTPenland

You simply need a flash that supports full E85, keep in mind the main reason to run full E85 on an otherwise stock B58TU is to save money at the pump, you will achieve optimal power on E30/E40.

But will e85 make more power than 93?

[RTPenland]

Originally Posted by opium340

But will e85 make more power than 93?

To run full E85 you'll need a flash tune - a flash will make more power on 93 vs full E85 on an otherwise stock car. A stock car cannot run full E85 but can of course run 93 so not really an apples to apples comparison there .

[Gryph8n]

Are you wanting to use E85 to maximize power output? As stated, with stock turbo and fuel pump, E30 is optimal to correct timing, cooling benefits and increase power output. For that you need a tune but preferably also a fuel flex ethanol sensor.

If you are wanting true max power from E85 then you are talking about fuel pump, port injectors, CANBUS, etc.

Clarifying your goals may be helpful.

[GD1981]

heres a general guide for stock turbo maximum output:

500-510whp: E50 tune
530-535 whp: E60 tune + PI (and motiv reflex)


Obviously upgrading the turbo will provide higher output. But like the guy above said, define goals/vision, and then strategy follows on how to get there.

[mike@x-ph.com]

You need a flash tune, upgraded downpipe, and an upgraded fuel pump to run straight E85

That said, I believe the power is the same as E50. so you are putting more stress on your fueling components without much benefit.

[RTPenland]

To add more detail:

I ran full E85 on my otherwise stock car with simply a flash. And it drove just like stock albeit with a little more power. The first generation's B58 fuel pump could not handle straight E85 but the TU can do it just fine. And unless you are going catless the oem DP performs pretty darn well compared to an aftermarket catted. Doesn't sound as nice but the performance is there.

[m440i804]

Originally Posted by RTPenland

To add more detail:

I ran full E85 on my otherwise stock car with simply a flash. And it drove just like stock albeit with a little more power. The first generation's B58 fuel pump could not handle straight E85 but the TU can do it just fine. And unless you are going catless the oem DP performs pretty darn well compared to an aftermarket catted. Doesn't sound as nice but the performance is there.

What year did TU start on the m440?