Couple Questions

[Jackpine]

Originally Posted by axlehead

ok so as far as custom tunes, I was wondering does anyone know the performance difference between the tunes? I want to get an 87 Performance tune and was also considering a 91 Performance. But is the canned 93 Perfomance as good as the 91? If thats the case I will stick with the canned 93 for play time. Also does the 91 Performance have better fuel economy then stock or the 87 tune? That is of course if I keep my foot out of it.

I can't give you specifics, but a custom tune will be better than the (same?) canned tune.

The canned performance tune is a 91+ octane tune, meaning you should only use it for gas that's at least 91 octane. If you ran 93 octane gas in it, You'd want to increase your timing by 1 degree. Bill would probably be able to make the 91 octane tune even more responsive than the canned tune. He would not try to sell you the tune if he couldn't do this.

Everyone says they DO get better fuel economy using a 91 octane tune over an 87 octane tune. This makes sense if you realize that a 91 octane tune is going to deliver more power (per unit of gas) than the 87. If you don't need that extra power, (keeping your foot out of it), you will use less gas. But, you MAY not save enough to make the high octane tune worth it. If high octane gas costs 10% more than 87 (about what it is here in Tucson), will you gain 10% or more in gas mileage? (You'd have to pick up that 10% to break even - I'd have to see a 1.55 mpg increase to make it worthwhile). I think this number IS possible, but I have not tried it.

I definitely picked up economy running the custom tunes over the canned ones. I added about 0.5-0.6 mpg while towing and close to 1 mpg on the highway when not towing.

Hope this helps.

- Jack