So i am about to send in my Evo to be converted and im looking at the custom tunes. I have a 04 5.4 with Airraid CAI, Magnaflow cat back, 2.5 level, 20" 33... I would like the most power i can get in one tune, then for a 2ed the best fuel economy.. Do you have to pick 3? Are the all based on fuel grade? I run 87 just about all the time. Should i bump up to 93?

 

93 performance will give you the most power. Period.

If you tow/haul anything over 2500 lbs you'll need a tow tune. You CANNOT use a performance tune for towing/hauling. Octane is entirely up to you.

87 performance will give you hp and TQ increases, but can be tailored to increase MPG.

You can order 1, 2, or 3 custom tunes. They can all be 87 octane or 91+ octane. You must use 91+ octane with a 91+ octane tune. You can use 91 octane with a 87 octane tune and increase your timing, but it's probably not worth the effort to get the timing exact.

 

I should do the 87 Performance for good power/fuel economy, a 91 performance for best power and leave the canned tow? Sound right?

 

I seldom tow, so that is exactly what I did. I use the 87 Perf tune almost exclusively. I am very happy with it for 40,000+ miles.

 

This is all opinion and gut feel.

If you NEVER plan on towing/hauling, then yes. If you do plan on towing/hauling, then you really should get a custom tow tune (to prevent any potential lean issues with your model year and A/M intake).

While the canned tow might be fine for the few times you tow, you've already spent the money for the the tuner, intake, exhaust, tires, leveling kit, etc., why cheap out ($60?) and take a chance? Just sayin'!

 

Good advice. I was forgetting the intake. I have the Gotts type mod, so not the same issues.

 

Great point.. thanks guys, made it easy on me!

 

Hey DD- let me know what kind of performance bump you get from the tunes. I have the same truck/engine setup and want some tunes but I'm curious what the net result is at our altitude. Thanks.

 

Will do.. Goes in tomorrow!