Exhaust MagnaFlow mufflers w/5.3 swap?

[bigmoe]

My stock Gen IV 5.3 has shorty headers, duals with no x/h pipe, Magnaflow XL 3 chambers and tailpipes over the axle and out behind the wheels. Love the sound on start up and slow power. Don't really like the hard throttle because it's quite "plappy slappy", not what I would call smooth and deep. I added some cheap resonators under the cab before the mufflers but it didn't really change it much. It's okay but I wish it was deeper and throatier.

[UniqueOdyssey68]

Hmm, from all the tech articles I'm reading and what MagnaFlow tech support emailed me today, the lack of a balance pipe (either H or X) on the LS/Vortec series engines is what is causing that "slappy" noise during hard throttle which is high in the RPMs. Those balance pipes are recommended for reasons to balance the exhaust pulses and even out/"smooth" the turbulence as the exhaust passes down the pipes. Might consider adding one and see if that helps yours, it should..
On the older SBC and BBC etc. this wasn't as much of an issue and actually produced a nice uneven "roar" pulse at high RPM, but the exhaust stroke scavenging and cam profiles are different in the LS. Reading up on this stuff has been kinda fun lol.

I think I'm going H pipe it seems to be less cost than a X pipe.
Thanks for the info on your setup.

Originally Posted by bigmoe

My stock Gen IV 5.3 has shorty headers, duals with no x/h pipe, Magnaflow XL 3 chambers and tailpipes over the axle and out behind the wheels. Love the sound on start up and slow power. Don't really like the hard throttle because it's quite "plappy slappy", not what I would call smooth and deep. I added some cheap resonators under the cab before the mufflers but it didn't really change it much. It's okay but I wish it was deeper and throatier.