so it has program for 87 91 and 93. We run regular 89 here in california. if i tune it to 91 or 93, do i have to put 91 or 93 gas in it?

 

That's usually how it works. The higher octane tunes get a bit more aggressive with the timing tables, and since dodge didn't see fit to include a knock sensor on our engines, running lower octane gas can give you spark knock to beat the band. Really not good for your engine.

 

alright so paying 10 cents more a gallon on a 91 tune will probably make my truck happier huh?

 

Yup... and if you don't drive it any harder (playing with the little extra power the octane/tune gives you), you will see a little mpg improvement to partially offset the higher cost at the pump... for me, I get an extra day (60+miles) out of a tank.

 

awesome, i plan to get the tuner when it becomes affordable. I not too much of a lead foot. I have to maneuver through quite a few inclines on my commute so that probably is what ****s on my mpg 10-11 is usually what i get, but then again my suspension is jacked beyond belief, another 3200 bill coming my way to fixx that. yay

 

If you have a lift kit on your truck what size tires are you running? And then what about gearing in your axles? What gears are you running right now? Regearing your truck will help your fuel mileage too.

 

I know , from reading , Hemifever seems to be the choice of many here . If you want a better SCT , and possibly cheaper , PM me . My guy fixes mistakes from Hemifever on a semi-regular basis , he was doing a fix today in fact .

 

why dont you post some info about this guy instead of just saying "my guy" pm me

 

Because I don't like to promote anyone , but , would give recommendation via PM as another option to use . I will answer your PM , just like I did for the OP

 

Hemifever has been around for a long time and has helped many people here on this forum. I'm sure like anyone he makes a mistake now and then. Is he given a chance to fix the issue? From my experience I would say he stands behind his work.

I'm glad your guy is working for you. Not trying to start a flaming war here either.