[K19BMW]

So i just discovered that a gas station 18 min away sells e85 (the next closest is almost an hour away) and have always wanted to run it for the added hp.

My question though is how hard is it to switch back and forth from E85 to regular gas if I didnt always want to drive 18 min to fill up? Can I just switch the tune setting on my jb4 or would I have to remove the e85 flash, inline lpfp, and the other stuff that running e85 requires?

[335NJ]

Using map 5 you can go back and forth, under a 35-40% blend, log often to make sure everything looks good. If you use a backend flash for E85, you have to have E85.

[K19BMW]

Originally Posted by 335NJ

Using map 5 you can go back and forth, under a 35-40% blend, log often to make sure everything looks good. If you use a backend flash for E85, you have to have E85.

So under a 35-40% blend I can go back and forth from E to regular gas if I am map 5.
Just to clarify though, if i have e85 backend flash I can only use map 5 with E? Or is it in order to use any of the maps (map1,2, etc) i will need E?

[335NJ]

Originally Posted by K19BMW

So under a 35-40% blend I can go back and forth from E to regular gas if I am map 5.
Just to clarify though, if i have e85 backend flash I can only use map 5 with E? Or is it in order to use any of the maps (map1,2, etc) i will need E?

I don't have a backend flash so I'm not very familiar with them, but I do know that if you have a backend flash for E85, regardless of what map you're on you must have E85, plus the stock LPFP can't handle much more than 35-40 anyway in most cases, so just stick with map 5 is my opinion. It will auto adjust for either fuel type when it sees it.

The sweet spot for me was E40, map 5 with my boost fail safe at 19psi since I would typically see 18-18.5 on that setup.

[Jnat]

Originally Posted by 335NJ

I don't have a backend flash so I'm not very familiar with them, but I do know that if you have a backend flash for E85, regardless of what map you're on you must have E85, plus the stock LPFP can't handle much more than 35-40 anyway in most cases, so just stick with map 5 is my opinion. It will auto adjust for either fuel type when it sees it.

The sweet spot for me was E40, map 5 with my boost fail safe at 19psi since I would typically see 18-18.5 on that setup.

Agreed!

[K19BMW]

Originally Posted by 335NJ

I don't have a backend flash so I'm not very familiar with them, but I do know that if you have a backend flash for E85, regardless of what map you're on you must have E85, plus the stock LPFP can't handle much more than 35-40 anyway in most cases, so just stick with map 5 is my opinion. It will auto adjust for either fuel type when it sees it.

The sweet spot for me was E40, map 5 with my boost fail safe at 19psi since I would typically see 18-18.5 on that setup.

Ok so i will shoot for around E40 and use map 5 without getting an E backend flash or new lpfp.

Although on the JB4 guide it says map 5 is 12-17psi. How are you getting 18-18.5?

[lemonpark]

Originally Posted by K19BMW

Ok so i will shoot for around E40 and use map 5 without getting an E backend flash or new lpfp.

Although on the JB4 guide it says map 5 is 12-17psi. How are you getting 18-18.5?

yeah I don't get it either but on map5 when my car has E85 in it the boost guage goes to 18-19 (well it seems like it does with the jb4 boost on fuel hijack)

[K19BMW]

Originally Posted by lemonpark

yeah I don't get it either but on map5 when my car has E85 in it the boost guage goes to 18-19 (well it seems like it does with the jb4 boost on fuel hijack)

Thats weird. Well if im able to hit 18-18.5psi im not gonna question it haha.

My only other option is to buy 100 octane race gas at this place that opened up on my way to work but that cost $10 a gallon

[lemonpark]

Originally Posted by K19BMW

Thats weird. Well if im able to hit 18-18.5psi im not gonna question it haha.

My only other option is to buy 100 octane race gas at this place that opened up on my way to work but that cost $10 a gallon

i've tried 100oct race gas (they dont sell it anymore at the place i got it from for some reason) but I was told its just 98RON (94aki for you guys in the US) mixed with some E85 to bring up the octane in it. I think it was something like 10-15% E85. But that was the United petrol station that I went too, might be different in the states.

[335NJ]

I have logs that show 18psi, which was before my clutch packed it's shit and said no more high boost

Then when 27_3 came out, I was lucky to see 16+ on the same fuel, but now with the newest firmware most people report they're back to where they were, I just can't confirm that since I'm dragging the clutch along until I can get it replaced.

OP, start with a low mix like 20% and log a few times when Map 5 has fully adapted to the new fuel, and make sure the LPFP and everything have room to work, then increase upto 35-40, that's how I did it anyway.

[K19BMW]

^^Thank you for the advice I will do as you recommend.

Just one more question though. Do I need to mix the 93 octane and E85 in a separate gas canister and then put it in my car? Or can I fill my car up with 93 and then just put a few gallons of E85 in?

[335NJ]

Originally Posted by K19BMW

^^Thank you for the advice I will do as you recommend.

Just one more question though. Do I need to mix the 93 octane and E85 in a separate gas canister and then put it in my car? Or can I fill my car up with 93 and then just put a few gallons of E85 in?

Negative, pump 93 in then pump E85 on top, it'll mix itself. I personally started bringing 3 5gal jugs with to the pump so I'd have some at home, I'd go get 93 at Shell, then go home and dump the E in.

[K19BMW]

Originally Posted by 335NJ

Negative, pump 93 in then pump E85 on top, it'll mix itself. I personally started bringing 3 5gal jugs with to the pump so I'd have some at home, I'd go get 93 at Shell, then go home and dump the E in.

Awesome! thank you for the help.

[335NJ]

Originally Posted by K19BMW

Awesome! thank you for the help.

Report back with your reaction to the new found power. Once the JB4 learns the fuel, it'll put a pretty big smile on your face

[wiskerbisskit]

I always just put in about 6 gallons of e85 and then fill the rest with 93. Burger doesn't reccomend more than 40% e85 mix. I have a 16 gallon tank so 10% of it is 1.6 gallons so 20% is 3.2 gallons. So about 6.5 gallons is about 40%. I just wait till I have about 10 miles left on the range put 6 gallons e85 in and fill up the rest with 93. After about 10-15 miles it gets mixed really well and your butt dyno will be off the chart.

[K19BMW]

I was planning on going yesteday but 10 inches of snow dumped on us and now tomorrow i think I am getting another 2 feet.

[BD_F22]

Originally Posted by K19BMW

I was planning on going yesteday but 10 inches of snow dumped on us and now tomorrow i think I am getting another 2 feet.

You must be on the East Coast, atleast it's drifting season!

[K19BMW]

Originally Posted by BD_F22

You must be on the East Coast, atleast it's drifting season!

Ya i am. Drifting is def fun (as long as you are safe about it) but I had just gotten all excited about running E only for mother nature to give me a big FU haha

[BD_F22]

Originally Posted by K19BMW

Ya i am. Drifting is def fun (as long as you are safe about it) but I had just gotten all excited about running E only for mother nature to give me a big FU haha

Yeah I hear you man! Just be careful running a ton of e85 during the winter.. They have a winter blend that sometimes isn't pure e85, its sometimes closer to e70. A few of my friends and I personally experienced this.

[K19BMW]

Originally Posted by BD_F22

Yeah I hear you man! Just be careful running a ton of e85 during the winter.. They have a winter blend that sometimes isn't pure e85, its sometimes closer to e70. A few of my friends and I personally experienced this.

Ya I read that online. In colder weather areas gas stations go from E85 to E70 but still have it labeled as E70

[e92_boost]

This is how I run e85
Map 5
Put 5 gallons of e85
Then 8 gallons of 93
Go to 1 speedo 7 tach reset fuel trim
Drive for 5 miles or so
Wot 3rd gear like 4x so the car and boost can get use to the gas
And you'll be set

[Turbo335iATX]

great info, was wondering about the mixture my self