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Mufflers

6K views 11 replies 7 participants last post by  Lemans guy 
#1 ·
Just wondering what mufflers people are using on their GTO’s, looking for something that sounds good for my 65 389 Tripower 4 speed car.
Would like to go with something with original dimensions, any help would be greatly appreciated
 
#5 ·
Years ago Jim Hand did a comprehensive muffler test on his performance oriented 455. on that combo he found Walker Turbo mufflers not only were among the top performers but also were some of the most reasonably priced. when i ran Walkers i liked their tone, aggressive but not harsh.
 
#7 ·
Make sure you return and let us know your exhaust manifold/pipe size combo and how you like the sound.

I used a 3" inlet/outlet Dynomax on my previous 400CI build, stock manifolds, 3" pipe with mufflers positioned just before the rear axle with turn downs. To me, they sounded great - not too deep nor too hollow sounding like some do. They did have a "drone" at about 2,500 RPM if you ran that RPM steady - which I would do because it was a tone that caught everyone's attention while cruisin' down the main boulevard. Less RPM or more RPM and the "drone" was not there. I will probably use the same set-up on my 455 build.

Placement of the muffler and tailpipes will also have an effect on sound quality. Had a 1954 Buick with a stock 322CI and put a set of Corvair Turbo mufflers in front of the trans crossmember. Gave it a really deep tone and one that got me pulled over for loud exhaust. Ran a built 409CI and ran a full exhaust using the Corvair Turbo's, 3" pipe, with tail pipes that ran into a 3 1/2" straight pipe that I ran out under the bumper. The 3 1/2" pipes amplified the sound and I got pulled over multiple times with the police officer suggesting I needed to add resonators to my legal exhaust to tone it down.

So other factors can influence the exhaust sound even if 2 cars use the same mufflers. :thumbsup:
 
#12 ·
I use straight thru manga flows and manga flow resonators behind them......makes a great sound and you stilll have the straight thru flow for power.....the turbo mufflers make a u-turn inside the muffler so can reduce the sound a bit..

My 460 engine needed the extra quiet of the resonators, a low rumble....the magnaflows are really nice. On more expensive Borla mufflers they do the same thing, straight thru with a resonator behind if desired...

Good luck....
 
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