[sigterm2.0]

So, don't flame me... I am still getting used to this load based tuning...

But I have a thought and would like to know if it's sound, or a bad use of the technology...

OK, so I have a TU pump (My bad, I didn't realize that TU couldn't handle E50), running BM3, so the Stage 2+ E50 map with E50 would peter out... But I was thinking, if I used the FlexFuel enabled E50 map, and ran the adequate E40 that my pump can handle with the FlexFuel sensor feeding precise ethanol blend information to the DME, could I run the Stage 2+ E50 map and have the FlexFuel code dial it back, ideally, gaining a bit more usable power than I get with the Stage 2+ E30 map alone?

...or am I off base and this is a bad or unsafe use of the FlexFuel technology?

...and for those using a FlexFuel sensor with BM3, does it's trimming happen as overall corrections in the datalog, or does it trim target advance first, and then the DME will make corrections as normal from there?


Thanks for your consideration...

[nosam1g]

lol ... just sell tu pump , get a dorch stg1 prob super cheap now below 800$ or just fill up e46..47 etc .. its not much of a power diff

[DieselDuck]

Just try the e50 bm3 ots and log it and see if it actually bottlenecks your tu hpfp first. It's not 100% sure it will

[n55david]

Contact bm3 and tell them you have the tu pump, send them a log and they will send you a new map..

Also

If you have the flex kit, yes you can run e40 and it'll adjust.

[sigterm2.0]

Does anyone know the process it uses to adjust?

For example, let's say at a given moment the map gives a 20 deg advance on an E50 tune. Then, let's say, the fuel sensor is saying that I currently have only 41% ethanol. Will the FlexFuel enabled map first retard the timing to let's say 16 deg advance... THEN the other DME functions with correct timing (which would show up in the logs as maybe -1 or -2 deg of timing correction) or does the FlexFuel enabled map correct AFTER the DME and this shows up at mega corrections like -5 to -6 deg of correction?

I ask because if it does it before the DME logic then load targets would still be intact. If it corrects after DME logic then things could get very messy trying to dial in tunes (not OTS maps) with this enabled.

[sigterm2.0]

Hmmm I guess we'll find out the answers. 😁😁😁

[sigterm2.0]

OK... Well I installed it... it was easy... plug and play.

No one will convince me that a FlexFuel sensor is a waste of money!

From the moment I pulled out of the driveway and rolled away the car pulled harder! As I was watching the live datalog, I saw that my ethanol percent... that was supposed to be near 30 for the E30 tune I was running... 19%!!!!

I had grossly overstimated the ethanol percent at the gas station where I filled up. It had to be somewhere near 60%...

Anyway, the ECU, now armed with this information, was able to correct it (I always ran the MultiMap, but I disabled the FlexFuel Sensor and told it I was running E30 manually). I never had knock, or corrections more than 4 or 5 degrees... so I thought I was pretty close... who knew!

Now with that 19% being fed to the computer, and it making its adjustments BEFORE the safety systems (it seems), I am getting corrections of only 2 or 3 degrees (most likely my plugs which I have new ones sitting here I will drop in this weekend (bought the car used with 84K on it, so not sure when the last plug change was).

I went to the gas station (had a quarter take left) to fill up, recalculated, filled up, and now I am at 47% ...I still stay with the E30 tune as my clutch is basically useless at anything more than 50% throttle... But even part throttle pulls so much harder than before. I am not sure what it's doing to adjust maps, but its great.

I'm still getting the 2 to 4 degrees of correction, but I can't do a real pull because it just spins the clutch. This didn't happen prior to the FlexFuel sensor giving the DME my E information. So, the adjustments that it's making actually DO make for a better tune than relying on the safety systems.

Soooo... now, what clutch do you all recommend (I don't want that upgraded stock repalcement, I want aftermarket suggestions that could hold the torque that accompanies around 750whp... don't want to upgrade again later.... stupid TU fuel pump)?!