Flex Fuel - N54Tech.com

pysical · **Flex Fuel -** 09-12-2017, 06:07 AM

Anyone know what the latest on Flex Fuel is? I am going with some GC turbos and want to take advantage of E85 on these but I don't want to go through the hassle of 50/50 mix and such. I know MHD was working on doing something that would take a 100% E85 tune and scale it according to the E content but wasn't sure. Does this exist for us yet?

And, if this does not exist and I have to get a tune specific to a E85 mix.. What sort of E85 blend can I run with PI, stage 2 LPFP, and running GC turbos.

Thank you.

Terry @ BMS · 09-12-2017, 07:41 AM

With the JB4 you can run its internal virtual flex fuel sensor, or add on a Fuel-IT physical sensor, and the JB4 will use either to rescale port injection as needed for the specific mixture.

With a Stage2 low pressure pump probably starting with a 50% mix is good and then evaluate from there.

pysical · 09-12-2017, 07:45 AM

Quote:

Originally Posted by Terry @ BMS

With the JB4 you can run its internal virtual flex fuel sensor, or add on a Fuel-IT physical sensor, and the JB4 will use either to rescale port injection as needed for the specific mixture.

With a Stage2 low pressure pump probably starting with a 50% mix is good and then evaluate from there.

Will JB4 modify timing, fuel, boost, etc to run higher HP based on the fuel-it physical sensor? I just want to run whatever fuel and let the car tune based on the E85 content. I don't want to have to mix 50/50, and do all sorts of different tunes.

Terry @ BMS · 09-12-2017, 11:19 AM

We have not tied the E85 value to the boost/timing mapping yet on the normal maps, but you've got map5 there which does that using an auto-tuning technique. We'll be adding another flex fuel auto tuning map in the near future though that relies on the E85 value.

bnk · 09-12-2017, 12:47 PM

Quote:

Originally Posted by Terry @ BMS

With the JB4 you can run its internal virtual flex fuel sensor, or add on a Fuel-IT physical sensor, and the JB4 will use either to rescale port injection as needed for the specific mixture.

With a Stage2 low pressure pump probably starting with a 50% mix is good and then evaluate from there.

As far as I understand, this does not work in many N54 335i cars.

Terry @ BMS · 09-12-2017, 02:06 PM

What does not work in many N54 cars?

erichale · 09-14-2017, 02:15 PM

He probably is referring to the KLINE cars.

bnk · 09-20-2017, 12:08 PM

Quote:

Originally Posted by Terry @ BMS

What does not work in many N54 cars?

These flex fuel features that you talk about. I was about to buy JB4 for getting flex fuel, but I was told that it requires a specific D-CAN bus. I don't know anyone in my neck of the woods who would have that.