Well, I thought I would play with the tuner last night so I tried the MPG tune. Holy Crap, lost about 50 RWHP It will make it more drivable in the Winter months, but WTF, Why would Diablo even offer something like this for the SRT?
Not seeing any improvement on the dash MPG monitor, maybe even worst as I have a couple long, steep grade on my normal commute. Real sluggish, and have to downshift on the hills. I will give it 3-4 tanks, but definitely a downgrade. Does make it easier to takeoff from a light without spinning.
I ran the DS FE tune on my 5.7L and noticed essentially no change in FE or HP. I get 28 MPG on long drives from Denver to SoCal. Less going up hill and exceptional going down hill, with the overall average at 28. Can't complain. In Denver area I use regular a lot as Mid is +$0.30 and Premium is +$0.60/gal. In UT it is +$0.10, which is more in line with what it costs to make higher octane grades of fuel.
Reinstalled the Diablo tune while the Kids were here for Thanksgiving, BIG Difference, but put ti back to the MPG one for now. PS: the Gas Mileage this tanks is going to suck
I run the 91 tune year round on my RT. just seems overall performance and reliability, and economy works with that one.
