[BrownBlazer]

So I recently installed the JB4 on my 2009 E92(and love the new found power).

I am trying to learn as much as I can about this tune. I did search this forum and the interwebz but not finding a solid enough answer to make me feel all warm and fuzzy.

So...should I test out some new fuel mixtures to see what this thing can do?
If so, what should I try out?

I am running the JB4 G5 board with just DCI FWIW.

And I know I can't run leaded fuel obviously, but can I run E85 ok? The place up the street has race fuel including 110(did not check to see if leaded or not yet).

Thanks for any help community.

B

[Jeff@TopGearSolutions]

Best advice is to email your tuner. AKA BMS.

You should not run more then 30% of E85. Map 5 would be recommended for that. I would not run leaded fuel either.

[hasta la pasta 27]

http://www.e90post.com/forums/showthread.php?t=688627

Check out the following link. I would say get to know it before jumping around. I still barely understand my procede

[MikeB@fftec]

Race is gas is also really nice to use as well other than the cost of $7 or more per gallon. I personally wouldn't recommend running leaded race fuel unless you like changing spark plugs, cats and 02 sensors more regularly.

[buster84]

Originally Posted by BrownBlazer

So I recently installed the JB4 on my 2009 E92(and love the new found power).

I am trying to learn as much as I can about this tune. I did search this forum and the interwebz but not finding a solid enough answer to make me feel all warm and fuzzy.

So...should I test out some new fuel mixtures to see what this thing can do?
If so, what should I try out?

I am running the JB4 G5 board with just DCI FWIW.

And I know I can't run leaded fuel obviously, but can I run E85 ok? The place up the street has race fuel including 110(did not check to see if leaded or not yet).

Thanks for any help community.

B

The Stock DME in the 335 are target based closed loop which means that your DME always asks for the correct amount of fuel. So if you run 30% or 100% it will adjust for it. Its not related to the tuner or device, its just how the bmw fuel system works.

The only issue is the fuel pumps, if your pumps cant keep up you wont be able to run high amounts of e85. typical pumps allow e30, but to really open up the fuel on the jb4 you want the cobb flash.

A walbro pump would definitely allow you to run more than 50%

[MasterWang]

Plenty of people run e85 with jb4, including myself.
Try with a low mixture, log, then post the logs here or ask Terry.

I'm at 45% e85 with 93 which is a bit high, but my car is kind of a freak and can handle that much without upgraded fuel pumps.