Hey guy's, I am starting to run e30 tunes from Matt .. Just wondering how many of u run a flex fuel sensor.. I went to the track this past Saturday thinking i had plenty of e blend around e35 or so and i sent data to Matt and said there was some knock in the run to add more e.. I sent away for a tester to see what is in the pump by my house and should have tomorrow.. Should i calculate around e40?? I know this is a question for Matt just looking for some input and what others are doing.. Thanks Scott.