69' Sidepipe cutaway...
Le Mans Master
Joined: May 2003
Posts: 8,875
Likes: 3,554
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
The C-3 long oval side"pipe mufflers were two tube cross-flow mufflers. the problem is they had very small flow tubes, so they were restrictive. Both flow tubes were staggered inside & they overlapped each other & cross-bled basically. To answer another question, I KNOW that a 3" OD straight muffler will fit under the OE style sidepipe covers on a C-3, but a 3.5" will NOT.
You can make 3½" pipes fit the fiberglass covers-I just used some ½" square tubing to space the cover out...
I'm running 3½" pipe w/ a 2½" inner pipe that will have an electronic cut out- or rather close the straight pipe and make the exhaust quiet by running through the outer pipe in a spiral w/ perfed stainless steel mesh and packing. This allows me to have completely open 2½" straight pipes = LOUD and the ability to not bother my neighbors w/ a flick of a switch-and it's variable between the two as well.
Artist rendition...
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I bought the Sweet Thunder 68-74. A little quieter than the 69 originals on mine, but a lot less raspy. Not sure if they flow better than stock but they are bigger internally.
I cut the rusted 69s in two to fit in the garbage. Just 2 tubes. An inlet and outlet tube encased in an oblong enclosure. Perforations allow flow between the 2 tubes. Of course my perforations were pretty rusted out and enlarged.
I cut the rusted 69s in two to fit in the garbage. Just 2 tubes. An inlet and outlet tube encased in an oblong enclosure. Perforations allow flow between the 2 tubes. Of course my perforations were pretty rusted out and enlarged.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I don't recall exactly. My reason to cut them was fit them in the trash, not inspect them. I only looked inside when about couple lbs of rust fell out.
But it seemed to me at the time, ease of production would be to simply run the full length and dead end at the end caps.
But it seemed to me at the time, ease of production would be to simply run the full length and dead end at the end caps.
Drifting
Joined: May 2005
Posts: 1,968
Likes: 44
From: East TN
Here's a picture of the inside of my SweetThunder 69' style with 2" inner baffles. Comes in the lower chamber 2 1/4" inlet into the first 2" baffle, then cuts over about halfway to the upper 2" baffle to the outlet.
Race Director
Joined: Jan 2005
Posts: 11,010
Likes: 166
From: Milford Michigan
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Le Mans Master
Joined: Feb 2011
Posts: 5,943
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From: Southern NH
Thread Starter
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,026
From: New Braunfels Texas
Great shot....thanks!
I E-Mail Sweet Thunder twice trying to get an idea....and they just kept sending photos of Hooker inserts and the flow charts for them....
Interesting...
Jebby