Jeovannie

iTrader: (26)

^+1 on that

4drboost

iTrader: (4)

Yes please let us get back to the OP.

97TSiAWD

iTrader: (4)

I'm not sure there is much more to cover on this topic. There is no general consensus as far as a "perfect" A/F ratio since some have seen power gains going leaner than 12.0 while others have not. Going leaner will certainly leave less room for error, especially as the ethanol content changes during the cooler months.

As always, each car and setup will have different results, and each driver/tuner will have different needs (i.e. all out power, safe tune, etc.) I've found it best to just try it on my car and monitor the results.

mrfred

iTrader: (50)

Perhaps its not quite that random. I think it depends mainly on the ethanol content of the fuel. True E85 does well at 12:1 and leaner. For Fall/Winter blends, as ethanol content goes down, good power is found at AFRs richer than 12:1. Vehicle-to-vehicle variability is always there, but it should be secondary to ethanol content effects.

awdboosted

iTrader: (30)

Just a side note. E85 runs much cooler and Evo Exhaust valve are inconel from the factory.

I agree with mrfred because its of the type of fuel you can running leaner but the benefits aren't any greater. I would also be concerned with running too rich because you can run into cylinder wash down.

TTP Engineering

iTrader: (465)

I have a hard time believing the stock exhaust valves are inconel.

crewdawg130

iTrader: (16)

+1....Yea not so much

I dont know but Inconel there not.

awdboosted

iTrader: (30)

Lets put it this way. I know some who is very fast that uses stock evo exhaust valves because they are inconel. I can't say who thou.

TTP Engineering

iTrader: (465)

Um, no.

crewdawg130

iTrader: (16)

The USAF agrees with you