Maybe it's just me or maybe it's that my heath tune is a more "all around" program (in all fairness, that's what I asked for) but I definitely wouldn't say I was "gobsmacked" with the difference.
Heck, I'll even go so far to say as I noticed very little, if any, difference in "power". The transmission schedule is where I've noticed the biggest difference from the stock "F" program.
Truth to tell, I didn't notice a difference (other than a bit smoother running and absence of dead pedal moments) until I put in the water injection to it.
I'm still trying to figure out why with only squirting H2O in the intake track. But when the Devils Own Progressive kit swings to "full on boogie" with heavy throttle and a downshift, this old truck absolutely opens it's eyes and GOES! It almost reminds me of a 2-stoke coming on the pipe or an old 80's factory turbo the way it hits....I can hear the difference and actually feel it. as ted Nugent once said about how his hunting truck goes, "like a booger with eyeballs".
With the water injection off, not-so-much.....so it's the injection kit more so than the program.
It also runs a little better (smoother) after a full on water blast. I'm guessing there's a little bit of cleaning action going on inside the combustion chamber with the added humidity/steaming action, but that's pure speculation on my part...can't back it up with anything besides my personal impressions.
Power levels seem pretty close to what the stock program runs (only measured by the butt dyno though). I've flashed back and forth a couple times to even out the perceptions of chenge due to a "new" program installed. Kind of the "placebo effect" principle. Same results every time. The Heath tune does tend to puff black on start, but cleans up right away. Something the stock tune never did. Clean start every time with the stocker unless I let off the key to early and fail started.
The heath program in my particular PCM was very confused by the vacuum wastegate system. Once it gave no boost at all, once it ran the boost all the way up to 20 psi, never the same results twice. It's definitely intended to by used with the TM. Keep in mind, I told Bill I was going to be using a TM, so maybe that part of the program was just not reworked or even looked at at all....
Truck does run smoother with the Heath program though. It also seems to work well in concert with the water injection, TM and exhaust to control EGT's but that could also be attributed more to the fact the TM runs more boost everywhere on the map than the stock system.
But as I said before, I asked for a daily driver with decent EGT control and "hill decent assist" (just holds the converter longer/lower) and that's what I got. Wasn't looking for a "Hot Rod". In my intended use, it seems to work well so far.
I've also been "tuning" EFI for a long time (although Diesel is a new thing for me), so it's pretty hard to "impress" me with a reflash/chip.
I generally am expecting changes in certain areas of the program before I even get one.
I can appreciate good work when I see it though. Heath gave me a nice all around program that seems to work well with very few areas that would need tweaking. It's pretty mild, but it all works nicely together....
