Anyone done this? My car did for one night when it was really cold and I didnt have my wideband in...It ran FAST though. Anyone think it would cause damage over time?

 

same here, i have not seen gains that would be worth running it that lean.

 

12.5:1 as the wideband shows when calibrated for gasoline? (lambda ~0,85)
Or real afr 12,5 for e85 (lambda ~1,3)

 

Calibrated for gasoline

 

...if you didn't have the "wideband in" how do you know what the AFR was?

 

Ethanol is an oxygenate fuel, so running leaner than what is generally expected (11.5-12.0)doesnt help. Running a little richer might not actually be bad as it is on gas though. Testing to follow.

 

That's about the AFR I run my car at. It doesn't seem to run that great if I go much richer than 12 or so.

 

my tuner has me tuned for 11.5-11.8 on e85 and it feels smooothhh threw the pull with no knock...but why go 12.5af, thats just too lean...

 

You mean not rich enough?

 

Same thing?

 

My butt dyno likes 12.5 WAY better than 12.0...Ill find out soon how accurate it is.

 

...how do you know you were running at 12.5 without the "wideband in"?

 

This is like the weekly Click & Clack puzzler....

 

I ran about 12.75-13:1 for the first part of last winter (induced by the cold weather). The main thing I noticed was that the car would often hesitate under accel because the stock ignition system wasn't able to ignite the lean mixture.

 

I put my personal evo on the dyno today to tune it for some added mods.

I ventured from 11.8 to 12.8 and there where no horsepower gains.

YMMV.