Test results: 98 octane vs E85

[Matt]

First one was from last year on my S14 SR20DET with standard T28, intercooler with 740CC and HPX MAF sensor

Second one done last night with my R34 RB25DET NEO with GT3071R, Tomei poncams, now upgraded to 1000CC injectors, HPX MAF sensor

These HPX are tuning up really well now with the custom resize curves in the 'Translation function generator' available in the software. The vehicle no longer has any reversion issues which we had previously with the Z32 MAF

[Matt]

What my content scalers ended up as (we did about four different variations E75, E40, E30, E20 in the time available)

[unex]

Matt, could you post full dyno chart where e20, e40 and e80 compared? I am very interested how much difference is between e40 and e80 in full rpm range. Thanks

[rick88ss]

What was the difference in boost for each ethanol blend or were all the runs at the same boost level?
Did you get to video any tuning sessions?

[Matt]

Same boost run over all sessions - I had intentions to do different boost levels with new code added to my R34 ECU to adjust boost by ethanol but I ran into problems with the MAC valve not venting enough from the actuator to work properly, so we stuck with a bleed valve instead

I only have the dyno sheets from the E40 and the E80 runs for the R34. The ethanol content was fluctuating in the tank during the testing sessions after initially dropping more 98 in.

For the S14 I'll have to hunt them down. Perhaps Pete has them

[rick88ss]

What is it that you try to tune for each ethanol percentage blend?
Do you tune each blend to 1 lambda on the wideband at low load and .8 at high load then adjust timing looking at peak torque? More or less

[unex]

I was interested in this picture full size: download/file.php?id=2613
but e40 vs e80 also would be nice to see. I am asking, because I think, that going from 98 to e40 gives more power, than going from e40 to e80

[rick88ss]

If keeping boost the same for each different ethanol percentage, how was the extra power made? I assume mostly by increasing the timing for the higher ethanol percentage. Alot more power can also be made by increasing the boost along with the timing as ethanol percentage increases.That is if you have forged pistons and such,correct?

[Matt]

Extra power through timing and E85 being awesome... you can increase boost on ethanol but you need a proper boost controller measuring ethanol content to suit to make this automatic. I'm working on something on my R34

S14 flex fuel graphs in full. We were going pretty lean on this one...

[STATUS]

lean is not too much of a problem on ethanol provided the timing it right, we run mid to upper 12's on some circuit cars to gain decent fuel mileage for endurance events.