Stoich values?

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12-02-2009, 04:44 PM
PurpleMinivan

Stoich values?

With pump gas having 10% ethanol now, how does this affect the tune?
12-02-2009, 07:28 PM
farmtruc

Quote:

Originally Posted by PurpleMinivan

With pump gas having 10% ethanol now, how does this affect the tune?

I did a little reading on this, didn't find too much info, but came to the conclusion that is doesn't matter.
12-02-2009, 07:35 PM
George C

all gas up here in PA has 10% ethonal all year round. in winter they switch to 15% and our mpg drops.
12-02-2009, 07:54 PM
PurpleMinivan

Quote:

Originally Posted by farmtruc

I did a little reading on this, didn't find too much info, but came to the conclusion that is doesn't matter.

Not doubting... just curious... but, I read that around here the stoich value is at 14.2 +/-2%/3% with 93 octane with 10% ethanol?? I checked the values in PE and it does change the AFR considerably to me anyway... What are they going to pull next lol. I set everything up with a different stoich value and made the other changes associated and AFR was good(12.7-13.0) in this case... LTFT were 900mv... blah blah... Meh, it may not matter and fall into the +/-2 and 3 percentile range that it really doesn't matter if everything's on the safe at the 14.6 stoich value.
12-02-2009, 07:56 PM
PurpleMinivan

Quote:

Originally Posted by Quik

all gas up here in PA has 10% ethonal all year round. in winter they switch to 15% and our mpg drops.

10% year round here also... I have noticed a slight drop in mpg in my DD as well:(.
12-02-2009, 08:00 PM
GasGuzzler

Eth has higher octane and less BTU so it takes more fuel for the same power. Seems like it would affect ragged edge set-ups to me but y'all know from experience.