i've heard that it can by gettin so hot and melting the cat after a while, but others have had no problems. i guess thats y most people just go with the race header or the full out svt conversion which is what i am doin
Don't have a direct answer for that. I have seen some totally slagged, and some seem to be fine. I would just go with the SVT set-up as well. It makes much more power than the shorty and doesn't cost musch more. Check here Mcnewsautomotive.com or Newedgeperformance.com
It might accelerate the breakdown a bit, but its not going to be instant death on the cat. I agree, go with the SVT header kit and RT cat. A shorty header with a stock cat offers practically zero gains over a stock header and cat.