Straight through mufflers

[1980RS]

What about the old SONIC TURBO mufflers?

Do they still make those?

I do not think they are being produced anymore but they were restrictive. I had a set on a car at the track it ran 13.07@105mph, when I dropped the exhaust the car ran 12.39@109mph no other changes. I run Dynomax bullets on the car now and it run quicker with them than without.

[F-BIRD'88]

What about the old SONIC TURBO mufflers?

Do they still make those?

I do not think they are being produced anymore but they were restrictive. I had a set on a car at the track it ran 13.07@105mph, when I dropped the exhaust the car ran 12.39@109mph no other changes. I run Dynomax bullets on the car now and it run quicker with them than without.

ok good report.. Mine are definatly more aggressive
Not so many tubes and more of the airflow can bypass the tubes altogether.

[autogear]

I use Classic Chambered mufflers with a crossover pipe. Sounds great, very vintage burble, a little bit of popping on decell, and thats without tailpipes, just turnouts

Very reminiscent of the Turbo Tube muffler (same developer) and the original chambered straight pipes of the late 60s. American made and very high quality. Couldn't be happier.

[MadBill]

Those GM factory chambered systems were ear-splitting; I don't know how they could have passed any sound standard! [But of course in that era there were also such systems as the GTO V.O.E. (Vacuum Operated Exhaust) that laid down all the baffles via what looked like a vacuum advance canister...]

[SpeierRacingHeads]

I had shorties, crossover, 3" into muffler with two 2.50 tailpipes. I tried a Flowmaster, Hooker, AP turbo, and liked the Spintech the best.

New system is long tube, 3" X-pipe into a 4" into muffler and 4" tailpipe. I tried a Flowmaster and hate it. Just today ordered a Dynomax 7" round. But have a feeling I should have just bought the Spintech and been done. So I have a 4" in/out Flowmaster and probably a 4" Dynomax Ultra for sale.

[Kevin Johnson]

Those GM factory chambered systems were ear-splitting; I don't know how they could have passed any sound standard! [But of course in that era there were also such systems as the GTO V.O.E. (Vacuum Operated Exhaust) that laid down all the baffles via what looked like a vacuum advance canister...]

Kool

https://www.hagerty.com/media/maintenan ... e-humbler/

[MadBill]

Every car is different, but a friend of mine used a 3" Spintech on the supercharged and inter-cooled Buick 3800 in his Fiero. It had nice sound quality but it was LOUD.

[MadBill]

...
Kool
https://www.hagerty.com/media/maintenan ... e-humbler/

Wow, it says they only ever built 240 GTOs with VOE! I saw a couple on the GM Oshawa assembly line in January 1970 when we were following the build of my pal's GTO. We thought the vacuum canisters hanging off the back of the mufflers were some weird emission control device; it was years before I saw them illustrated in a parts book.

[ptuomov]

Does case size and shape effect the sound level of straight through mufflers?

We had a long thread on closely related questions about straight thru mufflers: viewtopic.php?t=49628

The resulting sound here:

[bob460]

I had shorties, crossover, 3" into muffler with two 2.50 tailpipes. I tried a Flowmaster, Hooker, AP turbo, and liked the Spintech the best.

New system is long tube, 3" X-pipe into a 4" into muffler and 4" tailpipe. I tried a Flowmaster and hate it. Just today ordered a Dynomax 7" round. But have a feeling I should have just bought the Spintech and been done. So I have a 4" in/out Flowmaster and probably a 4" Dynomax Ultra for sale.

Spintech just like the flowmaster's are horsepower robbers.............but the spintech's do sound good. I like the extreme technologies mufflers myself.

[enigma57]

I use Classic Chambered mufflers with a crossover pipe. Sounds great, very vintage burble, a little bit of popping on decell, and thats without tailpipes, just turnouts

Very reminiscent of the Turbo Tube muffler (same developer) and the original chambered straight pipes of the late 60s. American made and very high quality. Couldn't be happier.

Just for kicks...... Got a wild hair and decided to experiment with chambered exhaust on the '57 when I drop the 292 inline 6 in. Thought I'd install the system and see how it works. And if there is any droning or if its too loud, maybe experiment with adding Helmholtz resonators (J pipe nodes).

Scrounged quite a few pieces of pipe and bends off e-bay including some long chambered 'Vette sidepipe replacement pieces from Classic Chambered having the correct inner tubing size. Have no bending mandrels here at home, so will need to cut and weld them to form the under car exhaust system for the '57 sedan when I fabricate the exhaust.

Will be running split manifolds and 2-1/2" duals all the way out the back with turndowns just beyond the rear bumper. And a crossover (balance) pipe up front near the transmission.

Best regards,

Harry

[enigma57]

Those GM factory chambered systems were ear-splitting; I don't know how they could have passed any sound standard! [But of course in that era there were also such systems as the GTO V.O.E. (Vacuum Operated Exhaust) that laid down all the baffles via what looked like a vacuum advance canister...]

The '70 GTO V.O.E. system is quite interesting, Bill. Never laid eyes on one but like the concept. In the mid '60s up in the Texas hill country, we were not very sophisticated when building cutouts. We'd pick up some long gas filler necks from the wrecking yard and weld them onto the exhaust pipes ahead of the mufflers so they 'just' stuck out under the doors and even with the rocker panels. Cut asbestos gaskets to seal them and picked up a few extra gas caps in case we dropped one. When it was time to race, we'd stop at a light, pull a heavy welders glove on one hand, open both doors and reach down and uncork the exhaust. No seat belts in those days in our early '50s cars, so it was an easy reach. Tossed the caps on the floor board. When the light changed, we were off to the races.

Didn't have cutouts on my own car though. Just ran straights turned out ahead of the rear wheels. DeSoto hemi with a '54 Dodge transmission and wider truck gears with no synchros. Had it in a '53 Henry J and later swapped it into a '55 Ford. Ran straights on both.

Happy Motoring,

Harry

[enigma57]

Too much time went by to edit my comments 2 posts above regarding chambered exhaust, but wanted to add this link. 'Before' is stock GM 'Vette sidepipes on a '65 'Vette with the 365 HP 327 engine. "After' is what the car sounds like with Classic Chambered's composite chambered/resonator replacement side pipes......



http://www.classicchambered.com/classic ... #corvettes

One of the options at Classic Chambered is what I would call a composite replacement section for 'Vette sidepipes. Comes in various inner core and outer diameters. Can be custom made with one side longer than the other if need be. These are 40" long body length and the owner of the 'Vette in the video has opted for sidepipes that are 1/2 chambered and 1/2 straight through resonator style mufflers with fibreglass packing (each portion being 20" in length).

Best regards,

Harry

[EDC]

HARM mufflers for the Cobra.

[ptuomov]

I'd definitely suggest adding a crossover (balance) pipe connecting the 2 banks, as its just more efficient on a full length muffled exhaust system. Either an H type or X type will work but make crossover same size as exhaust.

I agree with this. It'll likely give you a little more torque in a cross-plane V8 and suppress noise at the same time.