I am only on post #77 and feel like I tripled my E85 knowledge. Awesome discussion!

 

i just rescanned the entire thread. some things i understand better... others i still haven't figured out after 4+ years.

figuring out how to tune for power is the easy part:
- e85 likes boost... turn it up
- e85 isn't knock limited, i.e., its poosible to go right past mbt and damage the motor without ever seeing knock.
- rule of thumb for ign timing is use pump gas timing up to 4k rpm and race gas timing at peak rpm. blend in between.
- best power for me seems to at about 12.0:1, but there isn't much difference in power from 11.5:1 to 12.3:1. i get misfires at leaner than 12.5:1. i aim for 11.7-11.9:1 on the street. i'd run 11.5:1 on a road course.

what i still really haven't got figured out is timing and afr for optimum gas mileage. perhaps there isn't much variability because i see about the same mpg whether i try 14.7:1 or 15.7:1 or timing anywhere from 38 to 43 deg.

 

Points well taken sir! .... I am already on 33psi and I can feel the difference from adding 3 more lbs and 1 degree lol .... I want to finish the fueling next then move on to spark and see how it will run.
Thanks

 

What kind of timing are you guys running at full boost?

I am running E85 @ 40-42 psi @ 15* @ 7-8k @ 11.3 afr

not sure if im being to conservative with ignition or not?

I cant really go by my knock sensor... i have solid mounts and getting feedback thru sensor.
cruising at 1lb at 3k rpm getting spikes up to 3volts

 

I am on the stock block so 2-3* at peak boost/load then a quick ramp from 5500-8k to 18* by redline with ~12afr (gas lambda).
I am interested to hear what the others have to say as well!

 

^this is pretty much my exact setup right now at 27 tapering to 24 and it seems to really like it. I'm experimenting a little bit with my mivec up top too

 

Just trying e85 on my alt map..

Thank you all for the info!!!

The only real question i have is related to spool.

I keep reading about keeping timing the same in the spool range as pump gas, but how are people decreasing spool time with E85? Are they leaning the spool range vs the normal pump gas spool AFR's?

 

Bump for spool afr and timing notes

 

Decreasing spool has more to do with afr than timing. I run around 12.5 during spool and drop it to 11.5 shortly after peak load.

 

I wanted to switch to E85 but I'm scared of what I'm reading here, I know a car that runs with E85 so I was going use it as a baseline but it's in total contradiction with what you say (and I trust you way more)
car is running high timing with lean afr on a big turbo, seems wrong :/
edit : I only read a few posts on E85 here but I'm starting to believe the car was tuned with knock like gasoline :/ will read more tomorrow