[suby01]

Several tuning companies offer E30 gas octane tunes. And if youre reading this you may or may not know that E30 /E85 is relatively inexpensive compared to 100 octane and gives off pretty awesome power gains.

I know one option is if you have a gas station that actually sells E30 you can just use that.
But that usually is not the case, and you have to use E85 and mix it with your regular daily octane 91 or 93 whatever is available in your area.
Im in CT and we have only 2 gas stations that sell E85 and both of them are withing 10 min. of each other but they are 1hr drive away from me. So I have empty 5 gallon gas cans that I will be filling up for my fill ups.

I want to use this thread for all E30 discussions and your experience with the BMW brand.

The M40i gas tank size is 17.7 gallons.

1. I understand we should test the E85 gas for ethanol content, since it can vary from 60-80% ethanol content. Then we use this % of ethanol content in the E85 to figure out how much to mix with 93 octane in my example.

Is it okay to be off? Meaning you need to use 5.25 gal of E85 and remaining 93. Can we put 5.5 gal E85 or is that totally bad?


2.We may need to top off from 1/2 tank of E30 when going on a trip. What should the calculation then be of E85 and 93?


3. If at a location somewhere where E85 is not available and the next gas station thats close by is also far away and we want to fill up for example with 93 as an only option.
What tune map should we choose? There is still a E30 mix with 1/2 tank lets say and we will top it off with 93. So its definitely no longer a E30 mix. But we cant run the E30 down to empty because the next gas station is too far away.


4. What do you guys recommend for fill ups after the first fill up, run it all the way down to -- again? Is this recommended all the time or can we refuel at like 1/4 tank?

[Torinalth]

I am by no means a tuner for BMW cars, but i've tuned several cars in the past myself, and am using BM3 at the moment for the BMW while I learn the new platform. That said, heres my take.

1 - E can be from 50 at a minimum to anything more. for example the SHEETZ gas stations in my state routinely have E90 during the summer months and then E70 for their winter blend. So always test at the pump. I will typically not test the gas as I've only come across 1 station so far in so many years that is not e10, But yes youd use the e content to do the math to figure out how much of each you need to obtain e30 into whatever final quantity you desire.

yes it's ok to be off, just like it's fine to have crappy gas. but you want to set yourself up for success. I typically shoot for E33 and round up to make to the nearest half gallon to make it easier. just like adding a couple gallons of E to normal gas to get mild improvement on a standard 93 octane tune, the slightly higher e30+ content will accommodate for other issues.... but don't go too high.... no need to be exact, just close.

2 - again do the math. I use an app called FlexCalc to help. but in general if I am going outside my normal driving routine then I'll just run the tank down and flash back to 93. 93 is everywhere on this side of the US so it's a safer bet. when I have predictable conditions I go back to e30. But if you want to figure out exactly, just change your desired total end volume. its no longer 17g or 16g, its 8 or 4 or whatever, then calculate with the desired total volume to be that instead of a full tank to get the needed ethanol vs 93. gain flexcalc can help.

3 - If you are at e30 and you are low on fuel with no ethanol to be found, just flash back to 93 and fill up with standard premium. a bit of E in the tank is not going to hurt.

4 - again, read the above, think you are complicating it

For reference I've gone all in and am waiting for my two 55gallon drums to arrive so I can fill up a load of fuel to get me e33 blend on hand all the time while I'm home. should last me ~3 months with that quantity. so I'll fill up whenever I'm home at 1/4 tank or less, or more... whatever. my station is over an hour away and my 6x 6 gallon jugs were becoming a pain to refill so I was more 93 than I was e30.... this is my fix as I gain money for my dorch stage 2 pump

[suby01]

Originally Posted by Torinalth

I am by no means a tuner for BMW cars, but i've tuned several cars in the past myself, and am using BM3 at the moment for the BMW while I learn the new platform. That said, heres my take.

1 - E can be from 50 at a minimum to anything more. for example the SHEETZ gas stations in my state routinely have E90 during the summer months and then E70 for their winter blend. So always test at the pump. I will typically not test the gas as I've only come across 1 station so far in so many years that is not e10, But yes youd use the e content to do the math to figure out how much of each you need to obtain e30 into whatever final quantity you desire.

yes it's ok to be off, just like it's fine to have crappy gas. but you want to set yourself up for success. I typically shoot for E33 and round up to make to the nearest half gallon to make it easier. just like adding a couple gallons of E to normal gas to get mild improvement on a standard 93 octane tune, the slightly higher e30+ content will accommodate for other issues.... but don't go too high.... no need to be exact, just close.

2 - again do the math. I use an app called FlexCalc to help. but in general if I am going outside my normal driving routine then I'll just run the tank down and flash back to 93. 93 is everywhere on this side of the US so it's a safer bet. when I have predictable conditions I go back to e30. But if you want to figure out exactly, just change your desired total end volume. its no longer 17g or 16g, its 8 or 4 or whatever, then calculate with the desired total volume to be that instead of a full tank to get the needed ethanol vs 93. gain flexcalc can help.

3 - If you are at e30 and you are low on fuel with no ethanol to be found, just flash back to 93 and fill up with standard premium. a bit of E in the tank is not going to hurt.

4 - again, read the above, think you are complicating it

For reference I've gone all in and am waiting for my two 55gallon drums to arrive so I can fill up a load of fuel to get me e33 blend on hand all the time while I'm home. should last me ~3 months with that quantity. so I'll fill up whenever I'm home at 1/4 tank or less, or more... whatever. my station is over an hour away and my 6x 6 gallon jugs were becoming a pain to refill so I was more 93 than I was e30.... this is my fix as I gain money for my dorch stage 2 pump

Hey thanks so much for taking the time to reply in detail. Youre right I am over thinking this. I know I am very new to these fuel mixtures and I guess I am comparing it to Diesel in your car. Which is bad news. lol.

[_ink]

Torin has pretty much answered it all, the only thing I'll add is to ensure you log initially and periodically after that to make sure the fuel pumps are coping with the E-content.

Other than the power increase, the smell of corn juice is also great!!

p.s. I started a thread about upgrading fuel pumps, and this was a small part of that reason.

[foglem]

Just remember the actual energy density of these fuels is less. Your fuel economy goes down while yes, you can ramp power/boost pressure up. There are always tradeoffs.

[suby01]

Originally Posted by _ink

Torin has pretty much answered it all, the only thing I'll add is to ensure you log initially and periodically after that to make sure the fuel pumps are coping with the E-content.

Other than the power increase, the smell of corn juice is also great!!

p.s. I started a thread about upgrading fuel pumps, and this was a small part of that reason.

Good call on the logging portion. Is there anywhere I can share my logs? Because I have no idea what the lines bar graphs and schematics mean?

[suby01]

Originally Posted by foglem

Just remember the actual energy density of these fuels is less. Your fuel economy goes down while yes, you can ramp power/boost pressure up. There are always tradeoffs.

Yes I am also prepared for that. Whatever the minimum MPG is with stage 2 E30 Im sure I will manage to be below that. It all depends on how you drive. When I am modding cars my concern changes from MPG to SMG (smiles per gallon).

Anyone have any other great tips please feel free to share. Thanks to the guys that already posted.

[Torinalth]

Originally Posted by suby01

Good call on the logging portion. Is there anywhere I can share my logs? Because I have no idea what the lines bar graphs and schematics mean?

Feel free to post here. I've gotten pretty good at reading them, but for things I can't figure out I post in the F30 B58 forum in their log review thread.

[suby01]

Cool. I will do that which channels should I include in the logging for necessary info?

[Torinalth]

as of the current BM3 version for out platform (note we do not have the RAM pid values that the 3 series crew enjoys) I log everything except coolant temp, gear, LPFP act, LTFT, MAF, MAF HFM, vehicle speed, and WGDC. those pids are useful, but not for general well being logs. of course this is under the default menu, I don't turn anything on in the last tab.

[suby01]

Cool. Ill try it with my 93 map first. Thanks

[Torinalth]

So, lets put a bit of an update. Last wee I went out and found me some fuel

using FlexCalc this was my prospective mixture I was looking to attain



Then I took my barrels, put them in a rented trailer and headed off to the pump about an hour away

The illustrious pumps



My bounty in the back



and what it came out to be after testing



Looks like I am at about 31-32, so just a little lower than E33, but I'll find out for sure once I get my Ethanol Content Analyzer (ECA) intalled along with my incoming Dorch stage 2 HPFP. Should be here in another week or so.

So as of now I was only able to get a single log and no Dragy results due to traffic and weather, but as soon as its dry and I have open road I'll do a 5th gear pull and dragy run to see how shes shaking out. Heres the log I've got for a reference point

2019 X3 M40i
BM3 Stage 2 E30 tune
ER catted thermal coated DP
MST intake
VRSF charge pipe
E31-E32 blend on 93 octane.

https://www.bootmod3.net/log?id=5f11...90c66625c372d0

So here's to more people taking the X3 to the higher rungs of performance.

[Alias1431]

Damn dude, hardcore.

[_ink]

Hell yes!! Great job!

will you be custom tuning it also? Would be great to see comparisons from the OTS vs Custom tune if you do, as this alone usually yields good results.

[Torinalth]

Not going to custom tune for a bit. I'm debating about going to the vargas gc turbo. If I go that route I'll custom tune to e50, but still debating. I'll probably reevaluate in the winter and if I decide against the turbo it'll tune the stock one to e50.

Also got a log of 5th gear. I'll have some of the 3 series guys take a look, but my map is dropping on the higher end and curious if that's just needing more wgdc or if I need to track a leak.

https://www.bootmod3.net/log?id=5f12...0b432a4784ebec

Also got a dragy time but I'll have to post that from my pc.

[Torinalth]

So..... got to the next step, purchased, received, and installed the Dorch Stage 2 HPFP, flashed to Stage 2+ E30 map with dorch selected for my pump setting (apparently net G series revision posted by PTF will have dorch1 and dorch2 individually, F3x series already has that). Anyhow.... I've got a winner. Below is a log so you can see the nearly perfect curves. but first, the pics!


















https://www.bootmod3.net/log?id=5f22...90c67f30eb14f7

[Torinalth]

Figured I'd drop these here. These are Virtual dyno graphs based on my logs in very similar conditions and corrected for appropriate temp and pressure at time of log. due to slight road imperfections they are NOT perfect, but they are pretty solid. note that this is JUST tune changes, all the hardware in my sig is installed at time of all the logs so its truly only tune changes. note that there is some torque disparity between some of the tunes. that is due to the factory TCU tune limiting the power levels down low. PTF is working on updating maps to eliminate it and open the low end better. this is demonstrated in my Stage 2+ E30 HT map that was tested on my car by PTF to figure it out on our platform. Anyhow this should help show the benefits of ethanol and secondarily of an upgraded fuel pump.

[suby01]

Originally Posted by Torinalth

Figured I'd drop these here. These are Virtual dyno graphs based on my logs in very similar conditions and corrected for appropriate temp and pressure at time of log. due to slight road imperfections they are NOT perfect, but they are pretty solid. note that this is JUST tune changes, all the hardware in my sig is installed at time of all the logs so its truly only tune changes. note that there is some torque disparity between some of the tunes. that is due to the factory TCU tune limiting the power levels down low. PTF is working on updating maps to eliminate it and open the low end better. this is demonstrated in my Stage 2+ E30 HT map that was tested on my car by PTF to figure it out on our platform. Anyhow this should help show the benefits of ethanol and secondarily of an upgraded fuel pump.

Hey you said PTF is working on adjustments, is this with the OTS map or are you already going with a custom tuner?

[Torinalth]

PTF is working on redoing all the maps that are running into this issue with torque limitation due to transmission involvement. So the next revision should be fairly huge. The issue is that if you follow PTF that also have irons in the fire for rolling anti-lag, storing multiple maps on a single flash so you can change maps on the fly, and add on flex fuel adjustments. so there is no timeline on when it will get revised. plus the G series always gets the updates after the F3x guys do

[_ink]

Originally Posted by Torinalth

PTF is working on redoing all the maps that are running into this issue with torque limitation due to transmission involvement. So the next revision should be fairly huge. The issue is that if you follow PTF that also have irons in the fire for rolling anti-lag, storing multiple maps on a single flash so you can change maps on the fly, and add on flex fuel adjustments. so there is no timeline on when it will get revised. plus the G series always gets the updates after the F3x guys do

Great to hear! I'm on the MHD camp and I'm sure they'll either be doing the same, or will fast follow.

I haven't tried the E30 map since installing the Dorch as I'm still trying to empty out the gas in the tank. But what were you experiencing from a torque limiting perspective?

[Torinalth]

Originally Posted by _ink

Great to hear! I'm on the MHD camp and I'm sure they'll either be doing the same, or will fast follow.

I haven't tried the E30 map since installing the Dorch as I'm still trying to empty out the gas in the tank. But what were you experiencing from a torque limiting perspective?

I'm sure MHD is doing it, MG flasher already released some of their maps with the torque limit fix and the antilag. BM3 is never first to the punch it seems, but i'm always so happy with how they implement stuff and handle concerns that I won't complain about not being on bleeding edge. I don't have an IG accont, or have some odd 300k followers to impress.

in regards to the torque limiting, lets see the below image. I got a couple new runs on and think I'm finally happy with my baseline summer numbers and how the logs look with the Virtual Dyno graph for apples to apples comparison.



Now, see the grahps. aside from the major outliers of my HT tune and the stock tune almost all the others have disturbingly similar torque curves and max numbers, but all the HP numbers fall in line with roughly what you'd expect with the differences in tunes? This is the issue we see with transmission limitations. The way the tuning tables work on the BMW revolve around torque tables (no, not the same as measured torque in a dyno sense) where the car "requests" a specific torque, and it attempts to achieve it via boost and timing (those have individual limits in their own tables). Well when the Torque Actual value gets to a specific point (I don't know that number) trying to reach torque requested the TCU intervenes and pushes torque requested back down so torque actual drops as well below the TCU "acceptable" range. thus the low end is very much blunted to be a very similar amount to all other tunes.

This is NOT a limit of hardware. The turbo, fuel, and air available are all able to deliver more (again see the HT tune), but the TCU limits it. From my understanding when the TCU gets involved it corrects it fairly hard and you get a dramatic drop in power so PTF in this case prevents the torque requested value from driving the torque actual value too high to keep it below the TCU happy ceiling. Also is why most of the tunes all make similar power until people run the XHP software (not available on our cars and many others) to remove this TCU cap. Once the TCU cap is removed, or in the case of the listed HT map it's tuned around finally, you can scale up the bottom end of the tune to where you are now hardware limited. much more boost in this case and I'd be seriously increasing my IATs and that would pull timing without more octane to help fight it or other cooling (meth, water, new IC core).

What all this means in practice, and how I came across it and brought it to PTF for advice was my dragy times for the stage 2 E30 and stage 2+ e30 were odd... the lower speed portions of my 1/4 mile were always better with the stage 2 while the upper end was better with the stage 2+. and this was repeated and backed by my logs as well. Is started testing when I noticed in general that the off the line feel of my new stage 2+ e30 map (post dorch install) was just lacking in feel but was always fine once I spun the engine up (now i know it was due to torque requested and actual being lower in higher rpms). I had traffic tonight so I'd have gotten a new dragy time to go with my new log. Now that I have my dyno plots normalized, maybe i'll go back and do dragy times for all of them as well so I have more apples to apples.

anyhow, hope this helped

[_ink]

Originally Posted by Torinalth

I'm sure MHD is doing it, MG flasher already released some of their maps with the torque limit fix and the antilag. BM3 is never first to the punch it seems, but i'm always so happy with how they implement stuff and handle concerns that I won't complain about not being on bleeding edge. I don't have an IG accont, or have some odd 300k followers to impress.

in regards to the torque limiting, lets see the below image. I got a couple new runs on and think I'm finally happy with my baseline summer numbers and how the logs look with the Virtual Dyno graph for apples to apples comparison.



Now, see the grahps. aside from the major outliers of my HT tune and the stock tune almost all the others have disturbingly similar torque curves and max numbers, but all the HP numbers fall in line with roughly what you'd expect with the differences in tunes? This is the issue we see with transmission limitations. The way the tuning tables work on the BMW revolve around torque tables (no, not the same as measured torque in a dyno sense) where the car "requests" a specific torque, and it attempts to achieve it via boost and timing (those have individual limits in their own tables). Well when the Torque Actual value gets to a specific point (I don't know that number) trying to reach torque requested the TCU intervenes and pushes torque requested back down so torque actual drops as well below the TCU "acceptable" range. thus the low end is very much blunted to be a very similar amount to all other tunes.

This is NOT a limit of hardware. The turbo, fuel, and air available are all able to deliver more (again see the HT tune), but the TCU limits it. From my understanding when the TCU gets involved it corrects it fairly hard and you get a dramatic drop in power so PTF in this case prevents the torque requested value from driving the torque actual value too high to keep it below the TCU happy ceiling. Also is why most of the tunes all make similar power until people run the XHP software (not available on our cars and many others) to remove this TCU cap. Once the TCU cap is removed, or in the case of the listed HT map it's tuned around finally, you can scale up the bottom end of the tune to where you are now hardware limited. much more boost in this case and I'd be seriously increasing my IATs and that would pull timing without more octane to help fight it or other cooling (meth, water, new IC core).

What all this means in practice, and how I came across it and brought it to PTF for advice was my dragy times for the stage 2 E30 and stage 2+ e30 were odd... the lower speed portions of my 1/4 mile were always better with the stage 2 while the upper end was better with the stage 2+. and this was repeated and backed by my logs as well. Is started testing when I noticed in general that the off the line feel of my new stage 2+ e30 map (post dorch install) was just lacking in feel but was always fine once I spun the engine up (now i know it was due to torque requested and actual being lower in higher rpms). I had traffic tonight so I'd have gotten a new dragy time to go with my new log. Now that I have my dyno plots normalized, maybe i'll go back and do dragy times for all of them as well so I have more apples to apples.

anyhow, hope this helped

Thanks for the detailed response.

It all makes sense in what you're saying here, and a good pick up from you in noticing the different characteristics in the upgrade in stage maps. Your experience here has actually also made me think that I should hold off on a custom tune until xHP have a transmission tune available for us, to maximise potential.

Looking at your dyno graph, it's interesting that the Stage2+ 93, pretty much did the same as the Stage 2 E30!!

Question: What is the HT tune?