Quieter Side Exhaust

[Lorne G.]

My 67 small block side exhaust needs to be replaced and I would love to have a quieter sound. I was told that Sweet Thunder produces a " Super Quiet " side exhaust for midyears. Has anyone tried this system and is it really 50% quieter?

Thanks,
Lorne

[Jim H.]

Re: Quieter Side Exhaust

Lorne, I'm running a set of Sweet Thunder original sound side pipes on my '66 427. I just went to ST's website to see if they offered a "super quiet" set and did not find it. Maybe it's a special offering they don't advertise on the website. Maybe you know. Any way, my original sound pipes are a vast improvement over my prior Eckler's loud set but, although a lot of fun for about a half hour, they are definitely not quiet and I regularly wear ear plugs on longer trips.

[Lorne G.]

Re: Quieter Side Exhaust

Jim,
they do not advertise the super quiet series but they are available upon request. Apparently they add a ceramic matting between the baffles and outer pipe which deadens some of the sound. I would like to get some user comments before I lay out over six hundred bucks.
Lorne

[Patrick H.]

Re: Quieter Side Exhaust

What brand do you have now?

I've heard that the side exhaust from Allen's is quieter, and I suspect there are comments in the Archives if you wish to search.

[Lorne G.]

Re: Quieter Side Exhaust

I just recently purchased the car and have no idea where the side exhausts were initially purchased. They were added by the previous owner about 13 years ago.
Lorne

[William F.]

Re: Quieter Side Exhaust

Really want a side exhaust that is quieter than original????

[Kenneth B.]

Re: Quieter Side Exhaust

I have GM NOS on my 2 67'S 390 & 435. I love the sound. At 70MPH it has a sweet purrrr. If I want a quiet time I drive my Ford F150 with the Sirius radio on.

[Lorne G.]

Re: Quieter Side Exhaust

So it seems that I can't have my cake and eat it too!

I am currently battling a lean surge condition which may be making the exhaust note seem a bit louder.

[Mike T.]

Re: Quieter Side Exhaust

Lorne - I was thinking your side pipes are quite old and maybe the perforated tube sections inside have corroded away adding to the sound but you just mentioned the PO added the side exhaust only 13 years ago and that's really not that long ago. Then again, do you know if he installed 'new' pipes or were they used with a lot of miles on them. A few years ago I had three Coupes with side exhaust, two were added, one was factory original. All were mild smallblocks. The factory pipes had a lot of miles on them and you could just see those perforated pipes I mentioned up inside and there wasn't too much left of them which I believe added to the sound they emitted. Also, are there any midyear owners living near you with similar engines where you could hear them side by side to compare?

[Lorne G.]

Re: Quieter Side Exhaust

Mike,
The previous owner purchased new side pipes 13 years ago. Good idea about comparing various engines and I plan on attending a Corvette show in a couple of weeks so hopefully there will be a few side pipe midyears there with similar engines for me to compare exhaust tones.
Lorne

[Patrick H.]

Re: Quieter Side Exhaust

If he added them, why not go back to undercar exhaust?

[Lorne G.]

Re: Quieter Side Exhaust

I love the look of the side pipes but I am leaning toward going back to the under car exhaust. When I purchased the car I was given the rear valance, some exhaust brackets, original rocker mouldings, and the rocker moulding brackets that were cut off. I don't think it would be too much work to go back to under car exhaust. Would I have to replace the fibreglass pieces that were cut off or can I just leave the body as is? I assume the rocker mouldings would cover the cut fibreglass area.

Lorne

[Mark E.]

Re: Quieter Side Exhaust

Lorne - I was thinking your side pipes are quite old and maybe the perforated tube sections inside have corroded away adding to the sound but you just mentioned the PO added the side exhaust only 13 years ago and that's really not that long ago.

"Quieter side exhaust" sounds a bit like an oxymoron. But like Mike says, my experience with straight through mufflers is that they get louder with age and use. Renewing them, especially with ones that claim to be quieter, may help quite a bit.

Maybe go from "really loud" to "noticeable but tolerable".