i just got my silvy and it has flexfuel with all my tuning what is going to happen when i change from 87 to flexfuel. i know that ethenol's stoichiometric mixture is 9:1 compared to gasolines 14.6:1. will the ecu make up for it

 

There is a table in HPT that returns AFR based on fuel composition (0-100% alcohol). Mine is 14.68100 across the entire board since I don't have a Flex Fuel vehicle.
http://hptuners.com/forum/showthread.php?t=9389
There's some good info here about tuning and E85.

Good Luck!!

 

thanx

 

there are adders for timming and fuel in your tune and you tank hs a sensor to tell the ecu whats up. you can add timming to your flexfuel part of your tune............................i think lol. i don't have a cop of your tune i thought i did.

 

i dont think it does