79lance

good idea getting the X4 and then downloading the app to monitor guages. definitely cheaper. I have another question for yall while were here. Say i put a bunch of 87 fuel in the truck, and halfway through the tank, i need to tow my trailer and want my 89 Perf/Tow tune. if i switch it to it, it wouldnt run right, would it?? because i still have 87 in there. same with 91 race tune. if i put some 91 in there and go play around, and then need to go to 87 the next morning to drive for 3 hours of interstate, can i switch?? cause i have leftover 91 still in it.

RLXXI

Do not run a higher octane tune with lower octane fuel. It's best if you do not change the tune unless you fill up from near empty.

You can run a lower octane tune on pretty much all fuels available, not the other way around.
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QwkTrip

It takes 2 tanks of fuel to dilute the old fuel enough to switch to higher octane tune. That's a lot of driving.... Hence, the reason why it is kind of pointless to be concerned about how many minutes it takes to flash the ECM with a new tune.

Find a really good tune and drive it all the time. People that switch tunes often do so because they haven't found a good tune yet.

79lance

ah, arite. this makes sense now. i was more imagining some deal where you just switch around all the time to whatever suits what your doing. haha but one tune such as the 89 perf/tow would probably good for a lot of things, so that i would mainly just run it. well yall definitely helped me understand all of this a lot, this is a great site. thanks !

RLXXI

That would be true if someone is filling up at 1/4 tank. When I change tunes I do so very near empty.
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tanked_darren

Cheaper than 30$

I think I paid less than 10$ for my ELM327

Scarlet

I went with the Livewire because I wanted the gauges. Even on those rare occasions now when I do run the stock tune, I leave it in place for the gauges.