upgrading e99 pcm
 

I currently am running XLE4 PCM in an early 99. I was looking into trying to find a PMTx to put in as I heard the tunes are better as everybody likes to work with that code the best.

However I also heard that a few years back that may have been the case, but not anymore. Supposedly since then there have been advancements in the e99 XLE4 that will make switching to a PMTx not worth the upgrade.

Is that still true? I'm willing to try a swap out with the PCM only if it will give me better results, but if tunes have improved to make it unecessary I wont bother. I was looking into the Pheonix. Currently I have exhaust, intake, superchips. Looking into possibly an HPOP next. Thanks.

You won't notice any difference in the way the truck RUNS by changing the PCM (especially after putting aftermarket tuning on/in one).

The difference comes in the way the shifting strategies (and most notably the torque converter clutch apply/release strategies). Truthfully, if you have no issue with the way the truck shifts and the way the torque converter clutch operates, then there's really no reason to spend the money on changing the computer.

If you're still considering changing it and also considering buying aftermarket tuning in the form of a chip (not a programmer), you don't have to find a bona-fide PMTx box.....any DPC-422 computer will work. When you buy tuning for a DPC-422 box, the aftermarket chip company will put PMT1 tuning on the chip. Programmers don't work that way, so if you're planning on running a programmer instead of a chip, you will have to find a PMTx computer to take advantage of the change.

Then assuming that I go with the Pheonix chip I could put in a NVKx etc then still get the PMTx shifting progam? Do you find the shifting that much better than if I stayed with the XLE4 I have now? I have been fine with it but then again I haven't driven many others to compare it to.

Also just to clarify if I get the Pheonix then add in a Terminator T500 would I need to have the chip reburned, does an upgraded HPOP make that much difference?

Thanks again for all your help.

If you install a PCM that's capable of running PMT1 programming (don't confuse PMT1 with PMT2/3 because in certain situations, there are characteristics of PMT1 that are far superior to PMT2/3) you will notice a BIG difference in the way the torque converter clutch apply/release strategy is handled between your XLE4 and the PMT1.

As for the high pressure oil pump, it's not something that's an "upgrade". I hate that word because it's used to mean "something that's better than stock". While many of the aftermarket replacement pumps for the 7.3L move more oil than the stock piece will, the only time you will notice that you're moving more oil is under high power demand conditions. The truck will run exactly the same under normal driving conditions. Keep in mind that if you install the pump and have a rolling idle issue afterward, you'll have to pay for custom tuning to take the RPM fluctuation out of it. It's not a problem, but it can be annoying to some folks. Otherwise, the truck will run fine.

Sorry last questions.

- Would the FU/Pheonix work without upgrading to custom tuning if there is an aftermarket torque converter installed?

- I was looking at a CKX0 as well as a NVK2 instead of my XLE4. Both of those are DPC-422 right? So if either was installed, when using the FU chip I would get the exact same shifting strategy as if I had a PMT1?

- The Pheonix programs are the exact same programs as the FU correct? You just get access to all of them with the FU whereas you only get six with the Pheonix?

Thanks again for all your help.

Have a good weekend.