Get rid of that soft-natured factory tune ... permanently!
June 15, 2014
First, lets be realistic about the performance gains on the 05-10 4.6L ... it will not be massive ... but with a custom tune the gain is noticeable. Just wanted to clarify that, since some people have reviewed these products like they will be burning rubber all over the roads at ease. No, that will not happen. Either they have poor quality tires, or they're dumping the clutch left and right. However, these tunes do give the engine a little more get up and go, and definitely make a 200% improvement in throttle response. After driving with any of these tunes, it is impossible to drive the car again with that mushy low-grade factory tune.
I was disappointed with the "soft" low-end power these engines make with a factory tune. I had a 5.7L Hemi in a 4K LB car, and that car had gobs more low-end power than our 4.6L Mustangs. Well, a good solution to our soft low end is a custom tune!
I selected the 91S, 93P, and 93R tunes. I've loaded all three tunes and have driven each about 60 miles. All the tunes greatly improve throttle response, feeling more like a cable operated accelerator, unlike the factory tune which is greatly delayed.
My street tune improved low end get up and go, and the car still pulls just as hard up top as the factory tune. Perhaps better, not too sure? The performance tune feels softer down low than both street and race tunes, but is at least a notch better than a factory tune. It pulls nicely up top, nothing mind blowing, but not anything I found greatly discernible over the street tune. The race tune seems to be the best tune of the three for performance gains and throttle response. It seems to make better low and mid power than the street tune, but up top I really don't feel it pulls any harder than the other two tunes? Maybe something is wrong with my tune file in that regard? Or it makes such a substantial gain in low and mid, that there isn't as much of a transition to top end pull as the soft low/mid tune from the factory? Still not sure? Anyhow, the throttle response on the race tune makes for a "touchy" gas pedal, but not anything I would consider difficult for daily driver use. It's true that it will increase the likelihood of a stall or lurch from a stop, but that is mainly because the throttle sensitivity is greatly increased and makes the driver more prone to oscillating their foot on the pedal. Of course the other two tunes are less touchy, but the timing advance and get up and go factor of the race tune, makes the increased touchiness of the pedal a non-issue. You just have to relearn the nature of the go pedal. That's all.
As far as fuel economy between tunes I can't say, as I haven't logged each thru a full tank of gas with conservative driving habits, because the improved stronger pull makes me want to use it for now. I will see eventually...
Overall this is a great product and worth the expense ... but only because this is the way these cars should have been tuned from the factory. BAMA had my X4/SF4 to me within a weeks time. The device is simple to use and leaves room still for adjustments, even to the custom tunes.