Another question that I have and might be good info for this thread is to take note that the summit/jegs axhaust kits do not come with an H or X pipe at all...How does that also affect performance with out having either? And how much louder is it?
Just for a point of reference: Before I put the 360 in my Barracuda I had a built \6 with 6 into 2 headers and a full 2.25" dual exhaust with glass paks and no cross over. The exhaust was to loud for me, you couldn't carry on a conversation at cruise, and at WOT it had a nasty sounding roar to it, like a hole in the exhaust.
Since it was much cheaper to had a cross over than to change out the mufflers I tried that first. I just welded in a piece of 2.25" tubing to connect the two sides (H). It completely changed the sound of the car. It had a deep throatie rumble at idle and cruise and at WOT it had kind of jet engine scream. I got many complements about the way it sounded. It didn't however make any difference in the power as measured by the butt dyno.
With the 360 I have the Summit 2.5" kit with the Summit X pipe kit. The engine overall is very quiet at cruise and there is no noticable drone in the 1500-2000 rpm range but still has a nice rumble at idle and noticable and deep roar at WOT. This replaces a 2.5" compression bent system with home made x-pipe and Flowmaster 50 series Delta Flows. Compared to the new system the old system was louder through out the rpm range and there was more drone in the 1500-2000 rpm range but it was not bad. The flowmaster mufflers sound good but I like the deep smooth sound of the Summit turbo mufflers better. There is no noticable difference in the power as measured by the butt dyno.
