exhaust gas distance
 

Anyone that has a real free flowing exhaust might be able to answer this question:

Can you stand 10 to 15 feet from the rear of your car and distinctly feel the exhaust pulses even at idle? I can.

10 to 15 feet??? at idle ...
Damn what do you have under your hood? :devil:
For me to have felt my exhaust from that far, I need to have the choke on, and that was when I was running my 2.5" system on a 12A. At idle, I used to feel it maybe just over a yard or so from the tailpipe.

12A, 58* streetport, long primaries dumped into a 2.5" single right before the rear axle, RB presilencer as a muffler.