buchnerj

iTrader: (19)

Whoa, just checked on this thread and realized all of the comments as of late.

To all who helped and are adding their insight, thank you very much. I have since converted to Speed Density and am really enjoying it. I have made the switch to 93 for the winter and won't be back on Ethanol until things warm up outside. I do drive this car on occasion in the winter if the roads get bad (AWD FTW) so I need it to be reliable.

The tune as a DD is really quite good. AFRs are consistent and I am just battling with some fluctuating AFR values in the mornings sometimes as one day it will be 35-40 outside and decent, and others it will be 8 degrees with a foot of snow on the ground.

Next log I take I will post up the graphs and timing/fuel tables. They have been changed rather extensively, but still, this 93 map is literally for getting from A to B with very little boost. I have only made 2-3 pulls that have peaked over 15psi of boost. One had some knock, but it has been cleaned up since then...

Thanks again

Kasey

iTrader: (8)

I think the mid range has to much timing, but I could be wrong. I would start there though.

speifer

Is that on a gasoline calibrated wideband? For those load values, I believe you may be running too rich. I'd say an AFR of 14 is fine, but 12 is way too rich; thats what you should be running at WOT in higher load cells.

Why is this an issue? My theory is that running rich mixtures of E85 tends to cause some very rich/wet areas in the cylinder end-gasses. Having very rich areas (prior to ignition) in a cylinder with liquid hydrocarbons causes detonation.

This is something that I feel is greatly overlooked in the car tuning community. Most of the tuning focuses around ensuring the engine doesn't get thermally overloaded, which then leads to detonation. I.E. running too lean at WOT, or too advanced ignition timing.

I recommended leaning out your fuel in that region of your map and see if that helps.

hotrod

Sorry for bringing this thread back from the dead but I just want to share a bit and also give thanks to the super knowledgeable folks who gave input. I was having the exact same problems as the thread starter and it had been driving me crazy for WEEKS. Here are my mods:

Galant VR4
EVO 8 ECU
EVO MAF
EVO Knock Sensor
T3/T4 60-1
Tial Wastegate
Aeromotive A-1000 w/ fuel cell
FIC 950's
FMIC w/ 2.5" pipes short routed
3" exhaust no cat

That's it for the bigger items

After going through the thread and retorquing my knock sensor (it was in too tight) to 15 ft/lb, I reverted back to the stock EVO fuel and timing tables. I then went through my high octane timing tables and smoothed everything out so that there was no more than 2-3 points difference in adjacent cells. This helped a bit but I still had the spikes in the problem area. So I went and took 5 degrees out in the 2500rpm/90load area. Smoothed out the cells again and went for another drive. I tried every possible combo that cause my knock spikes and the knock light never came on!

Thanks for the time all of you spent troubleshooting the problem. It was hugely informative and is still helping people

Lion_Sam

This is become annoying.
My Evo IV have stock injectors with Aeromotive In-tank fuel pump and stock cams.

It seems like high knock (4-6, sometimes 8) happens when throttling from idle to half-open or more, at revs over ~3500. If I trying do the same from idle revs, it's nice - almost no knock.
With WOT knock is very low too, sometimes no knock at all.

So, I'm think, that's happens because of low fuel pressure at partial throttling. I mean that pump does not have time to raise required pressure for current boost.