how lean are you guys going? under vacuum im at 14.x

 

Is your wideband tuned for reading e85 ? 14.anything with e85 is really really lean. You should be somewhere more around 11-12

 

^^^ wrong. Tune to same AFR's as you would on Gas.

 

yeah please try to be informed on the topic before responding to questions.

 

A bit harsh JC. Not many people understand this AFR vs Lambda issue. Recognize that the better term is "gasoline equivalent" AFR since all O2 gages read in Lambda times a fuel correction factor.

If by cruise you mean under 0 psi then you can go to at least 16-17 eqAFR with E85 since detonation risk is only a concern at high boost (and temp) levels. Just ensure that your ignition is strong enough to avoid a lean miss.

 

I am doing 14.0-14.3 AFR cruising after my last tune.. Drives great..

 

E85 Stoic is 9.765 :1
petrol stoic is 14.7 : 1

if your petrol /gasoline mode AFR is reading 14:1 and you are running with petrol in the tank

then 14/14.7 = lambda of 0.95


if your petrol AFR gauge is reading 14 and you have e85 in the tank

then the wideband is still reading a 0.95 lambda

but is using the factor of 14.7 to the lambda value to produce the number on the
( petrol/gasoline ) AFR scale

if it was flipped in its program to display as E85 AFR instead ( some do )
then it would scale it thus
0.95 lambda x 9.765 = 9.3:1 E85

though it may be best to stick your gauges instead to a lambda display and learn to tune from that if there is any variance in your e85 pump blends

//


im using LPG, and my equivalence is 15.5 :1
.. and mine idles at 1.00 lambda and cruises at 0.95 - 1.00..

 

If the e85 can cruise as lean as 16 or 17:1 does that get the gas mileage Close to gasoline?

Is anyone doing a "lean cruise" on e85 under light boost?