Double Wall Exhaust

[Mark E.]

Which Corvettes and/or engines had double wall exhaust?

Why did Chevy do this? Minimize heat transfer? Quieter? More durable?

Does anyone today make double wall exhaust for our cars?


I posted this recently in Ken Hoffman's thread "D981 Starter Solenoid". It was a bit off topic, so I'm adding it here as well:

"I've heard (maybe in the TIM&JC?) that the original exhaust pipes in our '70s were double walled. Nobody (that I know about, and I've looked) makes reproduction, double-wall exhaust systems for these cars. I've also read (again, maybe in the TIM&JC?) that the exhaust note is different with the double wall construction.

"I believe Chevy used double wall exhaust to reduce heat transfer from the pipes to the engine and passenger compartments. Maybe another reader who knows more can confirm/deny."

Years ago, I owned a 69 Cadillac that suffered from a collapsed inner wall in one of the exhaust pipes. It took a while to discover this was the cause for the engine running poorly.

[Edward J.]

Re: Double Wall Exhaust

Mark this is a good question, I can tell that GM did it for quite a while, and it was a you say it was used quite the exhaust note. and did cause some headaches when loss of power was a problem back when no one had ever seen this issue. I myself was a Gm mechanic and had my run in with this problem and can tell I spent many hours with trying to fix the issue the first time I saw this.

[Joe L.]

Re: Double Wall Exhaust

Which Corvettes and/or engines had double wall exhaust?

Why did Chevy do this? Minimize heat transfer? Quieter? More durable?

Does anyone today make double wall exhaust for our cars?


I posted this recently in Ken Hoffman's thread "D981 Starter Solenoid". It was a bit off topic, so I'm adding it here as well:

"I've heard (maybe in the TIM&JC?) that the original exhaust pipes in our '70s were double walled. Nobody (that I know about, and I've looked) makes reproduction, double-wall exhaust systems for these cars. I've also read (again, maybe in the TIM&JC?) that the exhaust note is different with the double wall construction.

"I believe Chevy used double wall exhaust to reduce heat transfer from the pipes to the engine and passenger compartments. Maybe another reader who knows more can confirm/deny."

Years ago, I owned a 69 Cadillac that suffered from a collapsed inner wall in one of the exhaust pipes. It took a while to discover this was the cause for the engine running poorly.

Mark-------


The original exhaust pipes were DIE-FORMED. I believe that is the only way that "double walled" pipes could be made. Today, no one I know of manufactures die-formed exhaust pipes. Therefore, I would say that there are no "double walled" exhaust pipes available today (except NOS, of course).