Purchased 997.1 c2s with sports chrono, PASM, PSE.

Interested in improving appearance/stance. Can I lower and still retain functionality of PASM? Is there an alternative to filling the tire/fender gap aesthetically (wheels 19's) without lowering?

Secondly, I'd like to obtain a more aggressive exhaust note (love my Fister III sound on 993) without losing functionality of PSE function? Will sport cats do the trick?

 

you just buy lowering springs, and if you want porsche springs buy ROW springs
If you realize that us springs are made to make the car sit higher, the row spring is for the other countries where the car sits as it was designed to sit. So obviously the shocks were made for the car to sit lower than our us height

 

Lowering springs from Eibach or Techart will do the trick, keeping your existing PASM shocks. Or move up to PASM style coilovers - Bilstein Damptronics are very popular on the lower side of cost for coilovers, but still way more than lowering springs. There are also higher performing track coilovers too that keep PASM control - Tractive (via DSC) and KW come to mind, there are others too.

If you already have PSE, one popular mod is to turn it always on by disabling the valves. Search the forum for the details, disconnect one of the vacuum valve's electrical connectors. There is a Fister/Gundo mod to the non-PSE mufflers to duplicate your existing PSE sound, but that doesn't apply to you. A silicone replacement hose from the airbox to the throttle body adds some sound, including blocking off the smaller Helmholtz port on that same hose. Next up would be 200 cell high flow cats - that will definitely increase the sound. Pair them with the 997.1 X51 style headers and your existing PSE mufflers and it's awesome.

 

Excellent. I assumed it would be more complicated due to the PASM/PSE features. Simple lowering springs (or PASM style coilovers) and high flow cats (maybe paired W/ x51 headers) sound like a reasonable option. I'll research