dual exhaust on plymouth 6

so i have a 218 flat head 6 with reds headers and dual 1 1/2 in piping with one side straight piped and other with a glasspack, for some reason i get this sound coming outta the exhaust tips, sound like a exhaust leak around 500rpm but once you rev it the sound goes away but comes back once the rpms come down. also sounds like when you put your hand near the exhaust tip it makes like a swooshing noise sounds kinda like that. it pretty much only happens at idle. any idea what it could be? or how i could get rid of it

 

mine does a similar thing. i can actauly hear the sound change from the left/ forward to the right/rear as the rpms go up.

i am running two different length glasspacks

i thing its just because the engine makes different tones at a given rpm and with the unequal exhaust it going to make different sounds

 

alright here is a video i took maybe it explains it better, its pretty much only at idle
http://www.youtube.com/watch?v=a25J20WI58M&feature=youtu.be
i also tried turndowns and it made it worse since it was pointing to the ground, and side exits and still did the same.

 

I wander if it's firing order from one pipe to the other. my question would a H pipe help? good luck

 

wonder

 

I think that's what it doing, and the pulses just even out of of idle


Mine doesn't sound exactly the same at idle, because I run 1-3/4 pipe and have packs on both pipes. Mine has a little throaty'er sound at idle, but screams when you get on it. I actually thinking of adding a h pipe to it. I personally think that it sounds a little honda-ish when I'm on it.

 

Cutting the pipes off at an angle like a slash tip might help...

 

here is a video of mine with cast iron headers, 2 1/4 inch pipe, short 14 inch turbo mufflers and a cross over pipe about even with the middle of the transmission.

http://www.youtube.com/watch?v=AxfKQ4KMM9s

 

No, because of the firing order, the exhaust impulse sound wanders from one side of the pipes to the other. I'm in agreement that an H pipe might help.

 

so there is no way of getting rid of it unless i put a h pipe right? but then ill lose the rap am i correct?

 

how about a dump valve in the h-pipe. or even the electric valve hooked to a micro switch on the gas pedal.

idle= open h-pipe
on the skinny= closed/ true dual