After doing a lot of testing and research with this gas, and hearing of people's complaints of poor fuel economy, and poor running vehicles I have found a fix.

Because Sunoco Gas has 10% ethanol, the vehicle will actually be running leaner and the 02's will overcompensate for this and add extra fuel resulting in poor milage and drivability issues

Stoich for straight gas is 14.64:1 and gas/10% ethanol mix is 14.13:1. 02 sensor's have the ability to switch around any stoich point. but from the factory, is set to switch at 14.64 We have found that it is possible to switch the stoich point in the pcm to 14.13 and tune for the 10% ethanol mix in sunoco gas. This will allow the 02's to switch around the proper stoich/lambda point.

WOT AFR's will now change in the same way. Remember, AFR is just a math equation based on a lambda value. WOT AFR should be 12.0, or a lambda value of .82 (assuming straight gas). The lambda value of .82 with a 10% ethanol translates into 11.58AFR (14.13*.82=11.58) this will be the optimum AFR for a power adder vehicle.

Wideband airfuel meters come with a transfer function assuming you are running straight pump gas. They detect lambda and preform a calculation displaying an AFR. Because the wideband still has a pump gas transfer function the lambda value of .82 will still display as 12.0. Some wideband's can have their transfer function adjusted accordingly to display the proper AFR values based on stoich/lambda.

Just a bit of tech info for everyone

Sometimes I can write in a fury and I hate reading over my posts. If anything is confusing, i will be happy to clear things up

 

so, whats the solution, is it a tune, or is it the wideband? kinda unclear

 

The solution will be built into all of our tunes, so the 02's are switching around 14.13 not 14.64. A lot of tuners/shops have no understanding of these things or simply do not care

The wideband statemens were made to clear everything up because people will automatically think .82lambda of 14.13 should display 11.58 on the wideband and if they see 12.0 they will get all freaked out. I was simply stating that it will show 12.0 unless the wideband has a different transfer function

 

Meister... ummmm... I run 10% ehanol also... just ummm... what?

Could you put it in big captian dummy talk for me.

(Go firefly!)

 

The factory 02's will switch around any fuel mixture, but you need to change the stoich point in the tune