I just recently went through my first full tank with my new Xcal2 on 87 performance setting in my 2000 Supercab 4x4 w/ 5.4l. My first impression was that it's awesome! More power and firmer shifts and since I forced myself not to lead foot it I managed to get better gas mileage (15 mpg - 60% in town, 40% highway). It makes the truck feel the way it should have felt from the factory. Then two days ago, I went and filled up with Sunoco 93 and switched to the 93 performance tune. I didn't feel that big of a difference. The shifts felt a little different, but not much power difference. Should I feel a noticeable change or will I feel a change as the adaptive learning continues? I still need to change my O2 sensors but I wouldn't think that would make a huge difference. I haven't done my datalogging yet, hopefully this week I'll get that done and get it to Mike. I haven't tried the 93 towing tune yet, but I will at the end of the month when I pull my trailer on vacation. I just wanted to make sure that I wasn't missing anything on the 93 tune (maybe I'm already used to the additonal power between stock and 87 that I couldn't feel the increase)

 

Hi wemjr,

Actually, that's an excellent question - we have worked incredibly hard to get the most power possible out of our 87 octane tuning (well, of course we try to get as much out of any tune we can, but you get my meaning) in the 1997-2003 F-150's, so it already runs very well on the 87 octane tuning.

For example, we have already improved upon numerous things that cause delays and power reductions in all kinds of situations in the 87 octane tune - so then now the difference between the 87 octane tune and the 93 octane tune will take some more time to really work into it, and it will be just the sheer raw additional power gain. So we recommend giving it a few tanks. You also get used to the additional power pretty quickly, as it just feels natural, like it should have from the factory (like you said).

The difference in raw power between those 2 tunes is roughly about 15-18 HP - now in a big heavy truck, that may not "feel" like much - but it's there.

It's funny - some people swear they don't feel much on the 87 octane tune, but as soon as they drop in the 93 octane tune, they rave about it - and then others are like you, they do the 87 octane tune and notice that nice difference, and then wonder if perhaps it's supposed to be that much more gain in overall performance all over again when the 93 octane tune goes in, but it really doesn't work like that. See, we're already getting more actual increase in performance than what just the raw power gain would tend to indicate in 87 octane, thanks to all the other things in the PCM's program that we can improve upon - so the difference between that and the 93 tune is the sheer raw additional power.

I think that's about the best way I can explain it - I don't think you are feeling anything abnormal, I think it's just the nature of the beast and your perception of it, basically - and each person's perspective is a bit different.

I'm glad to hear you are enjoying your new tuning, don't forget to get those new O2 sensors in & thanks very much for your post!

Have fun,

 

"It's funny - some people swear they don't feel much on the 87 octane tune, but as soon as they drop in the 93 octane tune, they rave about it"

That's exactly what was throwing me off; it always seemed that everyone says 87 is just okay and that once they got the 93 tune in their truck turned into a rocket ship. Your explanation is exactly what I was thinking but it sure is comforting to hear it directly from the master tuner himself!

Thanks Mike!

 

I'd have to concur with your observation. I thought there was much more difference between stock and 87 octane tow tune than between the 87 tow and 91 performance. I had hoped to see better gas mileage with the 91 performance but it does not seem to do that either. I totally believe the raw power thing. It's just that, for the way I drive and use the truck, I get the biggest benefit gain from the plain old 87 tow tune. Since I don't run the truck hard, the 87 tow tune seems to make the most sense for me. I'm currently running the 91 Tow so it will be interesting to go back to the 87 Tow and see if I still feel the same way.

 

You're very welcome, as always!