I averaged over 36 on the drive to the Dragon with a best of 37.1 mpg. That was all highway of course. My daily drive I average 32-33 with 50/50 highway and city mix. Glad to hear most people haven't seen much of a change for the worse. I know that my driving is more spirited with the kit and I can vary my mileage based on how I drive. Too much fun not to play though!

 

I think part of the reason my mileage might be a little higher is I only use "ethanol free" premium. You might try some an see if it makes a difference. It's hard find though.

 

I run only 100% ethanol free. It is easy to find it here where I live. I think the other reason I don't get as good as Big Jim is because I have an auto instead of the manual. Always a little loss in mpg there.

Great numbers Big Jim!

 

Part of me still wonders if part of the big drop in my mpg has anything to do with the problematic ECU tune a few of us have right now.

 

I have had mine for about a year, and drive mostly rural roads and have observed a 32 MPG rating. Prior to the upgrade, was was getting 34 MPG.

Question to Xeraux, what is the problematic ECU tune problem?

 

something to do with the most current factory S1 ECU download (you dont get a CD that's VIN-specific anymore, like I did)-- automatics with the S1 kit are stalling out upon warm engine restart.

Back to the topic: my mileage has dropped about 2-3, but I could care less-- the fun factor more than makes up for it!

 

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