What size exhaust pipe?

[71 SE3834V]

Ok. I'm trying to quiet down my car a bit. It currently has what I believe are dual glass packs on it w/full tail pipes. Interestingly my Galaxie has the same size and shape "mufflers" w/full tail pipes and it's much quieter. Just a low rumble on that car. I figure the Charger's glass packs are "burned out".

Anyway, pipes don't look all that great and should be replaced. From what I measure they're 2 1/4" and from everything I read that was stock size. Would there be any benefit to going up to 2 1/2"? Also I read a bit about adding an H pipe to the system. Again is the much benefit to a pretty much stock 383 in the real world seat of the pants dyno testing? I know technically it would be beneficial but I'm asking for noticable better pick up or gas mileage? Not doing any street racing just cruising around and occasionally mashing the "Go" pedal.
Here are the need to know info:
'71 383 HP bored over .030. Low comp engine. Hp manifolds. Cam #'s are closely matched to the stock specs. 3.23 open diff if that matters.

Thanks for the replies.

[c00nhunterjoe]

2 1/4 is more then enough on a stock low compression motor. I would go with something straight through like the dynomax ultraflo or borlas fitted to an x pipe.

[crj1968]

I just put on a TTI system 2.5 " H pipe with Dynomax super turbos.  Sound good at idling and when opening it up and pretty quiet just cruising.

[Sublime/Sixpack]

Like already suggested 2 1/4" would be okay for your application, but if I was going to have new head pipes (or H-pipe or X-pipe, etc.) built and installed, I'd have them bump it up to 2 1/2" personally.

[Mopar Nut]

I had 2-1/4 exhaust with glass packs on mine when I purchased it, too loud for my taste. Installed a complete 2-1/2 tti system with "X" pipe and Magnaflows wide open mufflers. Real quiet (actually too quiet) until I push the go pedal, car runs better though.

[c00nhunterjoe]

2 1/2 on an 8:1 383 with manifolds is a waste and will take away from low end torque.

[Sublime/Sixpack]

2 1/2 on an 8:1 383 with manifolds is a waste and will take away from low end torque.

It won't be a waste if the car ends up with a 500 inch stroker in it in the future. Sometimes that happens. 

[71 SE3834V]

2 1/2 on an 8:1 383 with manifolds is a waste and will take away from low end torque.

It won't be a waste if the car ends up with a 500 inch stroker in it in the future. Sometimes that happens. 

Doubt that'll ever happen. Just had a rebuild on the matching #'s engine. Getting too old and worn out to be monkeying around with this stuff anymore. Gonna have to shop around for someone to do this exhaust.
Ok, sounds like I should just stick with the stock 2 1/4". Thanks.

[firefighter3931]

For a mild 383 the 2.25in pipe is fine. I'd go with a TTI system with an x-pipe and dynomax Ultraflow mufflers. 

The x-pipe will help with scavenging and the mandrel bent TTI exhaust will move the spent gasses out back more efficiently. 


Ron