I have an xcsb obs with 2005 lq9 swap. Flowmaster 2 into1 collector and 3" magnaflow muffler. No cats custom tuned to delete all smog and rear o2 . Engine runs great and have no issues except an annoying popping under acceleration anything over 3/8-1/2 throttle is has a stupid rapid popping sound. Any ideas? Please help.

 

Misfires?

 

Don't think so. Motor runs strong pulls hard. No shuddering or bog no hesitation..

 

Not having cat converters can for sure make it raspy/poppy then.

A resonator should get rid of the noise.

 

I'll look into getting one. Thanks

 

Change to a different muffler...

 

Since doing the lq9 swap I have had a flowmaster 10 flowmaster 40. Magnaflow bullet and magnaflow 9" oval all do it to some degree. The magnaflow oval makes the least amount of cracking

 

How long is the Magnaflow?

I think mine is like 22 inches long.

 

I believe it's 18" long. But it's not a super loud muffler. When it's not crackling it sounds great. Was thinking either an exhaust leak somewhere that I cannot find. Or maybe two unto one isn't enough exhaust for the 6.0? Idk though that's why I'm asking

 

Post a video.