Stoich AFR for E10 gas on 2003 Cobra tune

[WesDuenkel]

Pretty basic question here:

Doing a little tinkering with the tune on my 2003 Cobra. Stock pulley ratio, headers, exhaust, conical air filter. Noticed the "Stoich AFR" is set to 14.64, which is pure gas. We have E10 93 octane almost exclusively here. Would it make sense to change the Stoich AFR value to 14.08 to reflect E10? If so, is there anything else I should also change to reflect E10's higher fuel flow requirement?

Thanks in advance.

[murfie]

Yes it would make sense.

The sensors report lambda. So every fuels stoich is 1 to then.

The tune translates this into a air fuel ratio. That's what you are defining. Should be a minor difference, and nothing else needed to change.

[WesDuenkel]

Yes it would make sense.

The sensors report lambda. So every fuels stoich is 1 to then.

The tune translates this into a air fuel ratio. That's what you are defining. Should be a minor difference, and nothing else needed to change.

Yup, makes sense. I assume all the other tables are in Lambda...but wanted to make sure I didn't miss something. I'd expect every open loop situation to be slightly richer than current with E10, which might help improve tip-in transient throttle response.

Cheers.