slowlsx

iTrader: (26)

Anybody have a good step by step on adjusting a tune to E85. What I have seen is the following

Convert stoich to 9.7 and your Ve table should adjust properly if it was tuned correctly before. It will still need work but it should be close.

Or you can keep stoich 14.7 and just Tune like it was normal gas but add 30% to Ve and 35% to Ve under boost.

Also the obvious add a few degrees of timing to the total map.

Also would be a good idea to add 15% to the crank Ve and a few degrees to the timing at idle.

Anything else that needs to be done to get a base E85 tune or maybe someone could share their tune?

I just want to gather some solid information before I take the plunge.

KLUG'S SS

iTrader: (6)

Yes do it the right way and just change the stoichiometric table in the tune to match accordingly to the fuel you are running. And yes if your airflow tables were tuned correctly to begin with then everything should fall right in line.

Oh and not all "E85" blends are actually 85% ethanol, they vary from 70%-85% so this can alter things as well. Like for example if you set it to 9.7 but you actually had more of a 70-75% blend in the tank then of course you would end up running rich. Their is really only two ways to go about finding out what % it actually is, first get an ethanol test kit and actually test it, these test kits are relatively cheap and easy to use (I have one). Or the other option would be just to pay attention to your wideband or fuel trims, if they were within 1-2% and then you switch over to E85 and now they are off by a moderate amount then you know that you may need to adjust that stoich number a bit. Of course this is also assuming that you got your tank almost completely empty of the gas that you had in there before filling up with E85.

cfaluck13

iTrader: (4)

And this is all you really need to do? That just seems too easy. I wish my local e85 station wasnt so wishy washy with their supply

KY_BOB

iTrader: (2)

Don't forget that you have to have a fuel pump and injectors that can handle the increased flow. A stock motor might be OK. With FI, aint no way in hell. With a cammed and ported motor

KY_BOB

iTrader: (2)

I should have added, this is a tuning question, so I assume that you tune. Log the injector duty cycle to be sure. If they exceed or get close to 100%, you need higher flow injectors and to rescale the tune for them.

That said, my old AV, in good air, could reach 100-105% DC with 42#'ers in it on gas. There is no way in hell I could have run E85 in it unless I went to larger injectors. The stock 2002 pump couldn't even feed the 42's without an auxiliary in-line booster pump.

Dirty Dave

The quickest way to adjust for e85 is to adjust youre injector flow rate down. I usually decrease the flow rate by 12% then start it up and watch youre afr or fuel trims then adjust it up or down till they come in line. I usually hit it on the second or third flash. Ive done it the other way it takes longer and there is no difference in performance unless you screw up a good tune by messing with ve table. Efi live doesn't allow you to set your stoich to less than 10-1 and auto ve tuning is a pain when you change the stoich.