I bought a '99 F150 4X4 with a 5.4L V8 and 4-speed automatic. It came with a Superchips MAX MicroTuner and the 87 octane tune installed.

Exactly what changes does this tune make? Increase ignition advance? Change A/F ratios? Change shift points? I'm trying to squeeze every last MPG out of my pickup, so what tune would give me the best mileage? I've got the 3-program tuner, so I can choose from 87 octane performance, 92 octane performance, and Tow performance tunes.

I've also got a CAI and my IAT is generally right at ambient. Would this be cool enough to eliminate the detonation that would result in running the 92 Performance tune on 87 octane fuel? Is detonation all I would have to worry about in that circumstance?

 

The different levels change the timing to perform with the octane you are running. In performance mode the shift points are firmed up, I don't know about economy mode. I am on my 6th tank of Premium fuel [93 octane] and my fuel mileage has gained 1 mpg. With the winter mix that will probably turn into 2 mpg in the summer.

 

Go to superchips.com and look at that model.
It has all the specs.
I had the same 1715 installed on an '02 SCrew 2wd. I was getting about
15-16 city/ 19-20 highway. I also had a K&N filter and Gibson SI/SO exhaust.
Truck had just under 100K miles and was still getting great gas mileage. Traded for a '07 SCab STX 4x4. I'm actually selling my old tuner in the classifieds on this site.

 

So why do they not want you to pull a trailer when running the performance tune? Does it change the shift points considerably or is it the engine they're worried about? If I were to disable overdrive, would I be able to tow a trailer in the performance setting?

 

the tow tune has a richer a/f ratio to keep egt's down when towing

 

as well as different shift characteristics

 

What setting were you running in? Performance or Economy?

 

Usually ran the economy mode. Did a lot of highway miles.

I also adjusted the shift points so it wouldn't shift to a higher gear to soon.

 

Is there a limit to the number of times you can flash your ECM or how often?