New to E85...what do I need?

[tmillerx8]

Hi everyone! I purchased a modded 135i recently (almost fbo [no IC but has meth]). Anyway the car has had 93 octane its entire life and would like to try running E85 for a change. I hear that switching is quite simple, you need to start with about a 30% mixture and change the mapping on the JB4 to map 5.

I have a couple questions about this:

1. To gauge a ~30% mixture do I simply look at the needle for the gas tank? (fill it up at 2/3 of a tank)?

2. Any other adjustments I need to do with the JB4 other than switching to the auto tuning map (map 5)?

3. Could it be detrimental to the overall health of the car? Would there be any complications in running ethanol with methanol?



thanks in advance guys!

[135Pats]

1. http://www.intercepteft.com/calc.html

2. No, though if you are on the stock DME flash your ability to manage ethanol will be modest. The JB cannot adjust the fuel scalars, it just biases and lets the fuel trims adjust to the extent they can. It's fine for E30, but worth noting.

3. People have run ethanol on this platform for half a decade at this point. Not aware of anyone who has had serious issues that could directly be tied back to ethanol usage. The'res no inherent issue with both ethanol and methanol, though if you are spraying methanol as a means of supporting fuel delivery, you owe it to yourself to build a really solid system.

[tmillerx8]

Originally Posted by 135Pats

1. http://www.intercepteft.com/calc.html

2. No, though if you are on the stock DME flash your ability to manage ethanol will be modest. The JB cannot adjust the fuel scalars, it just biases and lets the fuel trims adjust to the extent they can. It's fine for E30, but worth noting.

3. People have run ethanol on this platform for half a decade at this point. Not aware of anyone who has had serious issues that could directly be tied back to ethanol usage. The'res no inherent issue with both ethanol and methanol, though if you are spraying methanol as a means of supporting fuel delivery, you owe it to yourself to build a really solid system.

excellent. thank you for the response. I do indeed have the newest back end flash so hopefully we won't run into any problems there.

[PawlyGuNNz]

Originally Posted by tmillerx8

excellent. thank you for the response. I do indeed have the newest back end flash so hopefully we won't run into any problems there.

hey which backend flash are you running? i am planning on running the e85 backend flash w e40-50 and try map 5 and map 7 but i have same mods as you except for meth... right now i dont have backend yet run map 5 and e30 but my fuel trims are maxing out on my logs.

[mike@x-ph.com]

Originally Posted by 135Pats

1. http://www.intercepteft.com/calc.html

2. No, though if you are on the stock DME flash your ability to manage ethanol will be modest. The JB cannot adjust the fuel scalars, it just biases and lets the fuel trims adjust to the extent they can. It's fine for E30, but worth noting.

3. People have run ethanol on this platform for half a decade at this point. Not aware of anyone who has had serious issues that could directly be tied back to ethanol usage. The'res no inherent issue with both ethanol and methanol, though if you are spraying methanol as a means of supporting fuel delivery, you owe it to yourself to build a really solid system.

Couldnt have said it any better

[Jeff@TopGearSolutions]

Originally Posted by 135Pats

1. http://www.intercepteft.com/calc.html

2. No, though if you are on the stock DME flash your ability to manage ethanol will be modest. The JB cannot adjust the fuel scalars, it just biases and lets the fuel trims adjust to the extent they can. It's fine for E30, but worth noting.

3. People have run ethanol on this platform for half a decade at this point. Not aware of anyone who has had serious issues that could directly be tied back to ethanol usage. The'res no inherent issue with both ethanol and methanol, though if you are spraying methanol as a means of supporting fuel delivery, you owe it to yourself to build a really solid system.

135Pats ---> Thread Killer.

Good job

[135Pats]

Aw Shucks

[tmillerx8]

Originally Posted by PawlyGuNNz

hey which backend flash are you running? i am planning on running the e85 backend flash w e40-50 and try map 5 and map 7 but i have same mods as you except for meth... right now i dont have backend yet run map 5 and e30 but my fuel trims are maxing out on my logs.

I'm currently on the BMS Race flash which is less aggressive than the e85 flash. Does this mean a 30% mix would be optimal for this tune?

[PawlyGuNNz]

Originally Posted by tmillerx8

I'm currently on the BMS Race flash which is less aggressive than the e85 flash. Does this mean a 30% mix would be optimal for this tune?

Yes you are correct... E30% mix is fine for race flash from what I understand up higher would be e85 flash... Which I may try but I still have oem lpfp so see how my car runs w map 5 and may try map7

[ecpoli77]

I am also new to the e85 game. how do you set the car up to run e85 but arent required to use it all the time? I am getting the fuel pump upgrade and flex fuel wires

[cbl117]

is there any issue with adding 2 gallons of E85 when you fill up with 91 to bring the octane to 93?

[135Pats]

Originally Posted by cbl117

is there any issue with adding 2 gallons of E85 when you fill up with 91 to bring the octane to 93?

No issues. If you have access to E85 i'd always recommend adding 2 or 3 gallons to bring up the octane headroom.

Log diligently, of course. But with a minor mix like that you'll get a viable bump in octane and in-cylinder cooling without running into any serious fuel pressure issues.

Do anything within reason to avoid 91. I honestly wouldn't feel comfortable giving this motor full load with that "gas".

[Helltime]

The backend flash stuff and maps kind of confuse me when adding E85 into the mix. When i first went with the backend flash alittle over a month ago I installed the pump flash. I run 35% E85 every tank on map 5. I am on stock down pipes, but have upgraded charge pipe/BOV and FMIC. My logs look good running this set up, but am I leaving power on the table by not using the race flash? Is it safe to use the race flash (will run logs anyways if i do to be sure) on 35% e85? Stick with Map 5 or change to another map?

[cbl117]

Originally Posted by 135Pats

No issues. If you have access to E85 i'd always recommend adding 2 or 3 gallons to bring up the octane headroom.

Log diligently, of course. But with a minor mix like that you'll get a viable bump in octane and in-cylinder cooling without running into any serious fuel pressure issues.

Do anything within reason to avoid 91. I honestly wouldn't feel comfortable giving this motor full load with that "gas".

Its the "serious fuel pressure" comment that scares me. My car is my only DD and I need it to be rock solid reliable. I only run Dinan software so I don't have the ability to log. Is it safer to use a few gallons of 100oct to bring it up to 93, or is there a octane booster that actually works and is safe for continuous use?

Also, maybe I'm not fulling understanding, but gas is already at E10 (at least in CA) so why not make it E20 and call it 93 octane gas?

[135Pats]

Originally Posted by cbl117

Its the "serious fuel pressure" comment that scares me. My car is my only DD and I need it to be rock solid reliable. I only run Dinan software so I don't have the ability to log. Is it safer to use a few gallons of 100oct to bring it up to 93, or is there a octane booster that actually works and is safe for continuous use?

Also, maybe I'm not fulling understanding, but gas is already at E10 (at least in CA) so why not make it E20 and call it 93 octane gas?

Semantics. If you do 12/2 91/E85 you won't have any issues with fuel pressure, trim behavior, etc. Scouts honor.

Adding race gas would do the same but it's expensive, doesn't do much to cool, and if leaded is nasty stuff.

And if you are out of warranty, i'd implore you to get a tune which you can datalog with.