It won't work well. Different programming. Why not sell the srt-4 S1 and then buy a PT S1. Keep in mind I've owned both an '03 modified GT and now own a modified neon srt-4. If you do attempt it you best have a wideband to check air/fuel mix as the intake manifolds are way different even though they are the same engine. The intercooler and plumbing is also different so that may affect programming, too. I just think selling the srt S1 and then buying the correct year PT S1 would be a better choice. You do know you can't even mix up the year S1 pcm with the wrong year PT. Also if you are looking for more power then look at the Diablosport Predator. It will hold 4 tunes. If you go that far I'd also want to have the correct year /model S1 pcm in the car so the tunes totally work. Have fun.
