Question: What affects exhaust sound?

[Bolisk]

I have a Small Block 70 and a Big Block 72.

On my small block, I installed an Allen's OFF ROAD exhaust. . .and it sounds fantastic!!! A nice deep thumping sound at idle. LOVE IT!!

I just installed the exact same exhaust on my Big Block car. . .and I am annoyed. . .it's dead quiet when compared to the small block.

Now baring any screw up by Allen's exhaust (sending me the wrong mufflers or something like that) why would I have such a difference in sound?!? It's got to be something with the engines. . .I'm thinking. Cam? Cam Timing?

The small block is an LT-1 CAM. . .and the big block is a stock 1972 LS-5 cam.

One of the things I noticed with the Big Block. The exhaust that was on the car when I bought it. . .was badly rusted. . .and I just waited for it to fall off before replacing it. Eventually one of the mufflers fell off. . .and I had to drive it a distance without the muffler. What surprised me was that even without the muffler. . .the car was crazy quiet at idle and cruising . .but was nice an loud under acceleration. So I'm guessing something in the engine has to be preventing the idle and cruise noise from being more desirable.

What gives?

Any input would be appreciated.

-Bolisk

 

[Hib Halverson]

Camshaft profile has a lot to do with how an engine sounds.

 

[imarivertwo]

No two engines are going to sound the same, especially when they're different years and sizes. Even if they were tuned to perfection, they're not going to sound the same, too many mechanical differences. If you want the BB to sound like the SB, your gonna have to experiment with some changes to the exhaust, engine, etc. On my 73 L-48, I have A CC exhaust with Magaflow mufflers and McJack's shorty headers . . . sounds great, to me.