Is is a '97 model or R/T, it can't be both b/c the R/T didn't come out until '98. '98 and '99 is the only year the R/T was offered in the 1st Gen Neon.
If you want a different sound, you can change the muffler, if you want more HP, you won't get any more than 2 or 3, the original exhaust on the DOHC models is good to start with. If you have a SOHC, you can pick up 5 to 7hp by switching to the DOHC muffler.