I'm looking to upgrade to a Mopar performance PCM this winter but the only one I can find is 92-93 through JEGS what's the difference between these years?

 

That's a good question and unfortunately I don't know what is different about the PCMs themselves. What I can tell you is that those years are all OBDI, so the PCM would plug in physically, and probably run your motor, just maybe not optimally.

The difference in the engines, or actually the features on the engines, is likely driving the need for different PCMs. So what's different that might affect PCM control:
1) 92-93 has a return style fuel system, 94-95 has a no-return system (I doubt this would matter to the PCM)
2) 92-93 injectors are sized differently than 94-94 (I can't recall which is larger).
3) 92-93 engines have better flowing exhaust manifolds than later years, and a larger Y pipe, etc.
4) Don't recall numbers, but I read somewhere that cam lift/duration in early 5.2 Magnums was slightly different.

There may be other differences, say with emissions gear, that have an impact as well.

 

If any of those does, it'll be the injector size.

92/93 is a 19# at 42PSI injector; the 94/95 is 24# at 43.5PSI. So it'll be running your 94/95 rich; it may well exceed what the ECU can correct for with the O2 sensors.

(I get this by a) checking the part numbers at RockAuto and b) checking the part number info at FiveOMotorSports.COM ... this information may be inaccurate, but it's worth keeping in mind.)

RwP

 

Thanks for the input guys. I had no idea about the injector sizes being different or that the older models used a return fuel system.