[714BMW]

Hi Everyone,

I guess I just wanted to do a write up regarding my experience running full E85 on my 2016 M235i 6MT with 29,000 miles. It seems there is very little information and limited examples of people running full E85 on stock turbo N55's so I thought I would share.

Why full E85?

Yes I know there's marginal gains to be had after around E40-E50 but I did not want to deal with mixing. In addition, these California gas prices are quite expensive so I wanted to avoid our poor quality ACN 91 gas altogether.

On the BM3 Stage 2 ACN91 OTS I was still receiving a decent amount of knock events as well as timing corrections. Additionally, my stock high pressure fuel pump would crash on just the 91 octane fuel. I wanted to do E30 at one point which only made my crashes worse (obviously) but the added power was rather addicting.

The Fuel Pump Scenario

The constant crashing of the fuel pump, both on OTS and a lower psi custom tune, was very unsatisfying and lead me to look into upgraded options. Please keep in mind that the vehicle in question was near 25k miles at this time (Now at 29k). After looking at various forum posts and talking with my tuner, I decided I would go with the Stage 2 HPFP from Dorch Engineering. Found a shop that has a crazy good deal on install after purchase through them and got it thrown in. Instantly the top end was pulling harder on 91 noticeably in 3rd/4th and the small misfires I used to get over 6k RPM were gone.

The E85 Transition

At this point I had the the capability of running an ethanol mix but was still on the fence. The cops in SoCal are relentless and will state ref cars that fill up at the closest ethanol station to me. Luckily a new ethanol station had opened up near me in a much friendlier car city and after talking with my tuner and how his n55 E85 setup had been running smoothly for over 6 months now, I went ahead and filled up the tank full of that sweet corn.

Revisions and Issues

I had mostly heard of people with LPFP issues when doing full E but also heard an equivalent amount of issues with people running upgraded LPFP's. (EKP among other issues). On the other hand, my tuner is running a similar flow-rate high pressure fuel pump and stock LPFP as well in addition to some of the cars he tunes. After doing a few cruise logs to ensure it was reacting well to the ethanol, we went ahead and started getting into the heavy pulls. We began near 15psi mid range until we got to around 19.5-20psi through revisions. A big issue at the beginning was throttle closure due to over-boosting since the lower RPM range (2500-3000) was very sensitive with the boost on throttle tip-in. Once we solved that issue, we ran into torque request ramping in extremely slow down low. This would cause torque actual to ride target and cause a timing dip on throttle onset. A few more revisions and this was squared away. The latest and ongoing issue is some minor clutch slip. In regular driving and occasional aggressive driving nothing is noticeable. On repeated hard shifts noticeable clutch slip begins to become present. I will be looking into a replacement soon but will hold onto this one for as long as possible.

Conclusion

The car is ridiculously quick now. Torque down low really throws you back and it keeps pulling hard until around 6k. It will begin to taper down after 5.7k but I shift around then anyway. The E station I go to regularly tests at E80 and has been solid so far. I have decided to not push the turbo more than 20psi as my WGDC is starting to reach low 90's on warmer days and the clutch slip mentioned earlier. Super excited with how it turned out and it has been quite surprising to see what I keep up with and beat on the streets now. It's been about 3 weeks so far and running strong.

I will be putting the car on a dyno most likely next weekend.

3rd Gear WOT Log:

https://www.bootmod3.net/log?id=6243...90c656b1dd4cf6

"Performance" Mod List:

VRSF Catless Downpipe
VRSF 5" HD Intercooler
VRSF Charge Pipe
Dorch Stage 2 High Pressure Fuel Pump
Stock LPFP
AFE Pro Dry S Drop in Filter
Custom E85 tune through Bootmod3
Valvetronic Axle-back Exhaust

NGK 97506 1 step colder plugs gapped to 0.022 (Got these with the intention of running 91. Will be gapping down to 0.020 once replaced)
Dinan Ignition Coils

(Driver Mod is still in progress)

@M235.eye on Instagram in case you wanted to see the "build"

-JM

[thejeremyman9]

Nice writeup. I have one main question: How do you plan to pass SMOG check in 2024 when your car is due? You will have to completely uninstall BM3 and the car wont run without the tune due to the HPFP.

Oh and who's your tuner?

[714BMW]

Originally Posted by thejeremyman9

Nice writeup. I have one main question: How do you plan to pass SMOG check in 2024 when your car is due? You will have to completely uninstall BM3 and the car wont run without the tune due to the HPFP.

Oh and who's your tuner?

Hey man, thank you!

I plan on selling the car once that smog check in 2024 rolls around. I will throw on the stock Downpipe, HPFP, and completely uninstall BM3 when I smog it back on 91. From what I've read (if I'm not mistaken) is that the intercooler and charge pipe should pass just fine. I'm looking at picking up an M2 competition from there and moving onto that as the future build.

My tuner is @keahih on Instagram.

[motivman]

Originally Posted by 714BMW

Hi Everyone,

I guess I just wanted to do a write up regarding my experience running full E85 on my 2016 M235i 6MT. It seems there is very little information and limited examples of people running full E85 on stock turbo N55's so I thought I would share.

Why full E85?

Yes I know there's marginal gains to be had after around E40-E50 but I did not want to deal with mixing. In addition, these California gas prices are quite expensive so I wanted to avoid our poor quality ACN 91 gas altogether.

On the BM3 Stage 2 ACN91 OTS I was still receiving a decent amount of knock events as well as timing corrections. Additionally, my stock high pressure fuel pump would crash on just the 91 octane fuel. I wanted to do E30 at one point which only made my crashes worse (obviously) but the added power was rather addicting.

The Fuel Pump Scenario

The constant crashing of the fuel pump, both on OTS and a lower psi custom tune, was very unsatisfying and lead me to look into upgraded options. Please keep in mind that the vehicle in question was near 25k miles at this time (Now at 29k). After looking at various forum posts and talking with my tuner, I decided I would go with the Stage 2 HPFP from Dorch Engineering. Found a shop that has a crazy good deal on install after purchase through them and got it thrown in. Instantly the top end was pulling harder on 91 noticeably in 3rd/4th and the small misfires I used to get over 6k RPM were gone.

The E85 Transition

At this point I had the the capability of running an ethanol mix but was still on the fence. The cops in SoCal are relentless and will state ref cars that fill up at the closest ethanol station to me. Luckily a new ethanol station had opened up near me in a much friendlier car city and after talking with my tuner and how his n55 E85 setup has been running smoothly for over 6 months now, I went ahead and filled up the tank full of that sweet corn.

Revisions and Issues

I had mostly heard of people with LPFP issues when doing full E but also heard an equivalent amount of issues with people running upgraded LPFP's. (EKP among other issues). On the other hand, my tuner is running a similar flow-rate fuel pump and stock LPFP as well, in addition to some of the cars he tunes. After doing a few cruise logs to ensure it was reacting well to the ethanol, we went ahead and started getting into the heavy pulls. We began near 15psi mid range until we got to around 19.5-20psi through revisions. A big issue at the beginning was throttle closure due to over-boost since the lower RPM range (2500-3000) was very sensitive with the boost. Once we solved that issue, we ran into torque request ramping in extremely slow down low. This would cause torque actual to ride target and cause a timing dip on throttle onset. A few more revisions and this was squared away. The latest and ongoing issue is some minor clutch slip. In regular driving and occasional aggressive driving nothing is noticeable. On repeated hard shifts noticeable clutch slip begins to become present. I will be looking into a replacement soon but will hold onto this one for as long as possible.

Conclusion

The car is ridiculously quick now. Torque down low really throws you back and it keeps pulling hard until around 6k. It will start to taper down after 5.7k but I shift around then anyway. The E station I go to regularly tests at E80 and has been solid so far. I have decided to not push the turbo more than 20psi as my WGDC is starting to reach low 90's on warmer days and the clutch slip mentioned earlier. Super excited with how it turned out and it has been quite surprising to see what I keep up with and beat on the streets now. It's been about 3 weeks so far and running strong.

I will be putting the car on a dyno most likely next weekend.

(My apologies if I went a bit overboard with my life story)

3rd Gear WOT Log:

https://www.bootmod3.net/log?id=6243...90c656b1dd4cf6

"Performance" Mod List:

VRSF Catless Downpipe
VRSF 5" HD Intercooler
VRSF Charge Pipe
Dorch Stage 2 High Pressure Fuel Pump
AFE Pro Dry S Drop in Filter
Custom E85 tune through Bootmod3
Valvetronic Axle-back Exhaust

NGK 97506 1 step colder plugs gapped to 0.022 (Got these with the intention of running 91. Will be gapping down to 0.020 once replaced)
Dinan Ignition Coils

(Driver Mod is still in progress)

@M235.eye on Instagram in case you wanted to see the "build"

-JM

Good to know that stock LPFP can handle full E85.. time to get rid of my Precision Raceworks stage 2.5 LPFP. I have noticed that my car seems to run better with the stock LPFP

[n55david]

See thats..that's... uhm.. yeah

So sure you can run full e85 on stock lpfp.. but that's also no different than saying you can run full e85 on stock hpfp.. which you can with a custom tune.

Think about that and let it sink in.

There is a reason we all went to a stage 2.5 lpfp.

[mike@x-ph.com]

I recommend you upgrade the LPFP as well before the stock one fails

[motivman]

Originally Posted by n55david

See thats..that's... uhm.. yeah

So sure you can run full e85 on stock lpfp.. but that's also no different than saying you can run full e85 on stock hpfp.. which you can with a custom tune.

Think about that and let it sink in.

There is a reason we all went to a stage 2.5 lpfp.

well... my precision raceworks stage 2.5 LPFP keeps giving me issues. I get HPFP codes in bimmerlink with it (something about pressure at release too low?), I DO NOT get those codes with the stock LPFP. Also, with stage 2.5 LPFP, running the same fuel (E50), some mornings, my car struggles to start up with it, but with my stock LPFP, my car starts right up EVERYTIME. I have already had the stage 2.5 LPFP replaced with another one, but new one does the same thing. I have tried using it with stock EKP and EOS BPM4, same result...so I don't know at this point.

[n55david]

Originally Posted by motivman

well... my precision raceworks stage 2.5 LPFP keeps giving me issues. I get HPFP codes in bimmerlink with it (something about pressure at release too low?), I DO NOT get those codes with the stock LPFP. Also, with stage 2.5 LPFP, running the same fuel (E50), some mornings, my car struggles to start up with it, but with my stock LPFP, my car starts right up EVERYTIME. I have already had the stage 2.5 LPFP replaced with another one, but new one does the same thing. I have tried using it with stock EKP and EOS BPM4, same result...so I don't know at this point.

That sounds like something else. Put the stock one in and see if it goes away.

[714BMW]

Originally Posted by n55david

See thats..that's... uhm.. yeah

So sure you can run full e85 on stock lpfp.. but that's also no different than saying you can run full e85 on stock hpfp.. which you can with a custom tune.

Think about that and let it sink in.

There is a reason we all went to a stage 2.5 lpfp.

Ehhhh. I would argue this is quite different.

The stock HPFP on EWG cars is a well-known limiting factor for ethanol and non-ethanol cars pushing more boost. The LPFP on the other hand, is not a known limiting factor. My stock HPFP was struggling and having major crashes with just E30 and it's widely reported that many cannot keep up around E30 stock. Obvious upgrade was needed and there are various forum posts of people running E50 or so perfectly with upgraded HPFPs so that solves that limiting factor.

There is very little to no information pointing towards a LPFP failure on EWG N55's, in particular the M235i. There is also very little information/reports of the LPFP failing to keep up with high ethanol content on stock turbo. If the LPFP could not keep up then I could tell from the fuel rail pressure dipping in logs which has yet to occur on my car. There's plenty regarding the PWG models in which that was a common failure point but not common on EWG examples.

On the other hand, there's many examples of people running into issues after upgrading the LPFP. Fuel-it and PR just to name a couple.

I am including a link below to a thread where Cary Jordan, highly regarded n55 tuner, responds to his own customer on Full E85 + PS2 stating that there is no need for a LPFP upgrade.

https://www.2addicts.com/forums/show....php?t=1808323

Does this wear the LPFP overtime? Most likely. But if there's no issue with how it's running right now and I have a tuner who runs the same setup with no issues for some time now, I don't see the point in upgrading. Logs are clean as hell and if it goes out then I replace it. No dips in fuel pressure in any logs.

Again, this is based on the research I've done across many forum posts and talks with my tuner. If there are examples of forum posts or other information indicating issues with the stock LPFP on ethanol there is a chance I missed them. Go ahead and send them my way so I can take a look.

Thank you.

[motivman]

Originally Posted by n55david

That sounds like something else. Put the stock one in and see if it goes away.

I did, and zero issues with stock one. I will run stock one for now, I plan on running Max of E60 anyways...so Do i really need a stage 2.5? From what I know, stock one taps out around E70...

[motivman]

Originally Posted by 714BMW

Ehhhh. I would argue this is quite different.

The stock HPFP on EWG cars is a well-known limiting factor for ethanol and non-ethanol cars pushing more boost. The LPFP on the other hand, is not a known limiting factor. My stock HPFP was struggling and having major crashes with just E30 and it's widely reported that many cannot keep up around E30 stock. Obvious upgrade was needed and there are various forum posts of people running E50 or so perfectly with upgraded HPFPs so that solves that limiting factor.

There is very little to no information pointing towards a LPFP failure on EWG N55's, in particular the M235i. There is also very little information/reports of the LPFP failing to keep up with high ethanol content on stock turbo. If the LPFP could not keep up then I could tell from the fuel rail pressure dipping in logs which has yet to occur on my car. There's plenty regarding the PWG models in which that was a common failure point but not common on EWG examples.

On the other hand, there's many examples of people running into issues after upgrading the LPFP. Fuel-it and PR just to name a couple.

I am including a link below to a thread where Cary Jordan, highly regarded n55 tuner, responds to his own customer on Full E85 + PS2 stating that there is no need for a LPFP upgrade.

https://www.2addicts.com/forums/show....php?t=1808323

Does this wear the LPFP overtime? Most likely. But if there's no issue with how it's running right now and I have a tuner who runs the same setup with no issues for some time now, I don't see the point in upgrading. Logs are clean as hell and if it goes out then I replace it. No dips in fuel pressure in any logs.

Again, this is based on the research I've done across many forum posts and talks with my tuner. If there are examples of forum posts or other information indicating issues with the stock LPFP on ethanol there is a chance I missed them. Go ahead and send them my way so I can take a look.

Thank you.

yup, I BELIEVE it. seems like EWG cars do not need an LPFP upgrade to run FULL E85. Just look at Steventalon1 signature. Running FULL E85 on custom tune with Pure stage 2 turbo:
14' M235i~ Pure stage 2 turbo, Wagner EVO III IC, VRSF downpipe/straight piped exhaust, Pure inlet pipe, CTS intake, PR coils, Dorch S2 HPFP, X-HP, Turbosmart dual port, BM3 Jordan E85 tune.

Now who wants my Precision raceworks stage 2.5 LPFP and EOS BPM4??? I will let it go for a good price... LOL

[thejeremyman9]

The later model N55 LPFPs are not a common "failure point" like earlier models where there LPFP would die for no reason, but there are a lot of people than ran into fuel supply issues after about E70, even on stock turbo, with tunes pushing 20+psi.

The HPFP is mechanical, so the limit is the limit. The LPFP is a traditional in-tank electric pump, so it seems there is some variability, which is why some people can run full E85 and others can't. Tuning may also be a factor, to a certain extent, both directly through boost target and indirectly through other parameters. Some people may also have better quality E85 and be hitting 85% - that last 15% can be the difference between having enough fuel and not.

[5w20]

Originally Posted by n55david

See thats..that's... uhm.. yeah

So sure you can run full e85 on stock lpfp.. but that's also no different than saying you can run full e85 on stock hpfp.. which you can with a custom tune.

Think about that and let it sink in.

There is a reason we all went to a stage 2.5 lpfp.

Originally Posted by 714BMW

Ehhhh. I would argue this is quite different.

The stock HPFP on EWG cars is a well-known limiting factor for ethanol and non-ethanol cars pushing more boost. The LPFP on the other hand, is not a known limiting factor. My stock HPFP was struggling and having major crashes with just E30 and it's widely reported that many cannot keep up around E30 stock. Obvious upgrade was needed and there are various forum posts of people running E50 or so perfectly with upgraded HPFPs so that solves that limiting factor.

There is very little to no information pointing towards a LPFP failure on EWG N55's, in particular the M235i. There is also very little information/reports of the LPFP failing to keep up with high ethanol content on stock turbo. If the LPFP could not keep up then I could tell from the fuel rail pressure dipping in logs which has yet to occur on my car. There's plenty regarding the PWG models in which that was a common failure point but not common on EWG examples.

On the other hand, there's many examples of people running into issues after upgrading the LPFP. Fuel-it and PR just to name a couple.

I am including a link below to a thread where Cary Jordan, highly regarded n55 tuner, responds to his own customer on Full E85 + PS2 stating that there is no need for a LPFP upgrade.

https://www.2addicts.com/forums/show....php?t=1808323

Does this wear the LPFP overtime? Most likely. But if there's no issue with how it's running right now and I have a tuner who runs the same setup with no issues for some time now, I don't see the point in upgrading. Logs are clean as hell and if it goes out then I replace it. No dips in fuel pressure in any logs.

Again, this is based on the research I've done across many forum posts and talks with my tuner. If there are examples of forum posts or other information indicating issues with the stock LPFP on ethanol there is a chance I missed them. Go ahead and send them my way so I can take a look.

Thank you.

• The M2/M235i LPFP may have more flow capacity than their 3/4 Series counterparts
• OP's tune may not be aggressive enough to require an upgraded LPFP. I understand it's running full E85, but IF it is targeting say 400hp and 420tq to the wheels then technically it won't need the fueling capabilities that others have seen and had LPFP fuel pump issues when running lower ethanol content with more aggressive tunes.

At a quick glance it looks like the OP's tune is a little softer than a Bootmod3 stage 2+ tune. Boost target is slightly softer in the lower RPMs and in the upper RPMs as well, plus it doesn't reach the same level of peak degrees of timing either.

[n55david]

Originally Posted by 5w20

• The M2/M235i may have more fow capacity than their 3/4 Series counterparts
• OP's tune may not be aggressive enough to require an upgraded LPFP

This is why I said you can run full e85 on stock fueling. I believe it's an option in mhd isn't it?

[5w20]

Originally Posted by n55david

This is why I said you can runnfull e85 on stock fueling. I believe it's an option in mhd isn't it?

I believe so. I understood what you were getting at, but others may have not.

[n55david]

Originally Posted by 5w20

I believe so. I understood what you were getting at, but others may have not.

Yeah for sure

[thejeremyman9]

Originally Posted by 5w20

At a quick glance it looks like the OP's tune is a little softer than a Bootmod3 stage 2+ tune. Boost target is slightly softer in the lower RPMs and in the upper RPMs as well, plus it doesn't reach the same level of peak degrees of timing either.

Yup

[ZM2]

So, you guys are telling me that I can pay money to get a custom tune that runs full E85 with less whp than an OTS map on E30?

Where do I sign up?

[714BMW]

Originally Posted by ZM2

So, you guys are telling me that I can pay money to get a custom tune that runs full E85 with less whp than an OTS map on E30?

Where do I sign up?

I think you're missing the point here. Wanted to run a map that minimizes knock, avoids pump gas, and is still quicker than an ACN 91 tune without having a flex fuel sensor. Absolutely did not want to mix as stated previously and did not want to max out the turbo which I also stated previously. I don't chase numbers. I said I would dyno it purely for reference and that is it.

[n55david]

Originally Posted by ZM2

So, you guys are telling me that I can pay money to get a custom tune that runs full E85 with less whp than an OTS map on E30?

Where do I sign up?

Yes.. you can do just this!! MHD ftw

[714BMW]

Hey guys,

Quick update. Boost has been holding well and car has been running smoothly on the latest revision. We decided to add some more timing as my clutch has been holding up well recently.

I will be taking the car to a dyno on Saturday to see how it does. I do not have a baseline dyno unfortunately. European Auto Source dyno'd a stock m235i on California 91 gas at around 305whp/320wtq for reference.

The dyno spot I'm going to stated they dyno manual cars in 4th, so I got a log in 4th gear just to test in case anyone wants to check it out. I went up to 6.5k rpm's but looks like BM3 only captured up to ~6.2k rpm. Anyways the link is below.

Says I'm hitting over 700 torque at clutch (actual). That can't be right

https://www.bootmod3.net/log?id=624d...90c63505079099

[AmuroRay]

Just install the base map, run it and then run with the tune. Actually, not sure how that would work with the full E85…