A question for those getting 18-20 mpg. Is your speedo correct with a GPS or a timed distance on the interstate? My computer was giving me 19-20 mpg readings until I started adding goodies. After 34" tires, 513 gears and a 3" lift it indicates 15 give or take. I've tried all of the different Superchip settings except the tow mode and they all give 15 mpg. I don't need the power after the 513 gears. I rarely go over 60 mph on the highway with slow starts and stops in town. There wasn't much of a change with either setting, but I don't get into the skinny peddle much. Before I'll believe a true 18-20 mpg on a JK with auto on 35 or 37" tires and a lift, I'll have to drive it myself. No offense.

 

Love mine, in the short time I've had it. Continual testing and and trying different things. I have 2 programs I use with success (pleases me) driveability performance, and very decent milage using both tunes and the right gas for both.
93tune with 91oct gas for speeds <65mph or short runs of 65 (off interstate driving) Driveability is great and milage pushes +18mpg.
87tune with 87oct for interstate driving is fantastic. Driveability is un-important as long as rpm remains 2k to 3k rpm and 65-75mph in OD with 4:88 gears and 35's.
( interstate driving) results are equilivent to the 93tune, with cheaper gas.
Using GPS to verify speed, seat of the pants can be questioned, but very pleased right now with mine.

 

I love the flashpaq. I prefer the tow tune the best. The high octane tune isn't worth it to me. Its 20 cents extra per gallon in TN. Always hand calculate your mpg. The dash display is worthless. I can get anywhere from 13.5 driving hard to 18 mpg driving decent on the highway.

 

Every station here has 93 octane. Some states I believe have special fuel requirements that limited the highest grade of commonly available gas to 91 octane. It sounds like your state is one of them.

I would not run the 93 tune with 92 or 91 octane fuel. Just give the 91 octane tune a try and see how you like that.

 

7'eleven carries it here, but I've run 91 and even 89 on my 93 octane tune with no ill effects or pinging or clonks etc.

 

What happens is the programmer changes the timing to run more efficiently with the higher octane. If you run lower octane the engine should “knock” or detonate under heavy load. However most newer engines have knock sensors that detect this and automatically retard the timing preventing engine damage from the detonation.

So if you tune for higher octane part of what you’re doing is advancing the timing then the jeep automatically retards it under load if it starts to detonate.

 

In round numbers every 2500 feet above sea level reduces octane requirements by 1, and of course the local filling stations will follow suits given their location.

 

This programmer is next on my list. I get about 13 maybe 14mpg after putting on the 35's.
I use my JK as a commuter for my 120 mile drive daily. I used to get 17.5mpg and those numbers are hand calculated. The biggest problem is the dead spot at about 40mph. At that point you have to put your foot into it. If I could get rid of that O would be sold.

 

Don't expect the superchip to improve your economy. It might, however, give you a little more power in the 91 or 93 octane setting.

 

I ran the 87 tune with mine when the Flashpaq came out for the 2010. It was ok, great improvement over stock. I then tried the 93 tune, and I have not looked back. For the gains I get it is worth a few dollars more for a tank of gas to me.