Air/Fuel questions

[garylovell]

Back when I bought my '08 Vette, non alcohol gas was readily available, so I'm sure the a/f map was set for the 14.7 stoich value. Highway mileage was up to 31mpg. This is no longer the case, and stoich for gas with alcohol is about 13.9 , and the computer is adjusting based on the older values. Can or should the computer be re flashed to that of a more recent year Vette? I guess I'm interested in keeping things "right" for the engine more than getting it up past the 436 range.
Would my vette benefit from one of the re calibration tuners such as Diablo Motorsports ? I'm sure this would enhance the performance when at WOT , but don't know how much they deal with the whole rpm range. I don't race the car.
Thanks for your inputs.

 

[Hib Halverson]

Most pump gas which is ethanol blended (some call it E10) is between 7% and 8% ethanol. I split the difference and use 7.5. Stoichiometric AFR for "E7.5" is 14.25:1 When I calibrate, that's what I set as the value in the stoic field.

As for whether or not the Diablo Sport handheld supports changing that value, I don't know.

I use HPTuners to calibrate and it does allow you to change that value.

 

[garylovell]

Thaks for the info !! Gary

 

[Hib Halverson]

You're welcome.
Glad to be of service.