original sounding mufflers

[Keith B.]

for dads 67 427/390 build he bought Corvette Central exhaust complete exhaust system. it fit perfect with no real problems. So today we started the motor for the first time we started the engine up. the problem is the mufflers sounded very mellow and sounded like the stock style mufflers (walker) on my 396/360 Chevelle.

should those to cars/engines sound the same? or is the CC exhaust that fair off

[Edward J.]

Re: original sounding mufflers

Keith, I had C.C. stock style mufflers on my 63 327 solid lifter car and was just to quite for me, so I decided to install there N11 mufflers which really sounded like a true muscle car of the 60/70s and there are sound great under acceleration and are quite at cruise speed.

[Keith B.]

Re: original sounding mufflers

The car is a factory L36,M35 with C60. So it could not have N11

[Edward J.]

Re: original sounding mufflers

Keith, won't just a N11 muffler work??? even though my 63 did not have the N11 option I installed the N-11 mufflers. I know that corvette central has a video of there N-11 system on You tube, and its a big block 67 which really sounds great. I was only stating my 63 stock style mufflers from C.C. sounded like your car.

[Keith B.]

Re: original sounding mufflers

I'm sure the N11 mufflers would work. But my question was did a BB Corvette sound like any other BB cars back when they were new

[Edward J.]

Re: original sounding mufflers

Keith, I Don't think that any B.B. cars (corvette or Chevelle etc.), could really sound the same as Pipe lengths and muffler sizes and exhaust tips were a different size. I do know the GM factory pipes were of carbon steel and double wall construction. which makes for a different sound.The pipes made by the corvette venders is a singe wall.

[Jim T.]

Re: original sounding mufflers

Edward do you know how much of the exhaust pipe system had the double wall construction from the factory and if replacement exhaust pipe from GM parts counter were double wall construction like the factory installed?

[Edward J.]

Re: original sounding mufflers

Jim, I have a friend that has a rear set of NOS 2 1/2 mid year pipes and they are double wall construction. They weight a lot more than the replacements from the corvette venders. Also the construction as far as I remember it was double wall construction front to back.

[David K.]

Re: original sounding mufflers

My 65' 365hp solid lifter car has a set of GM 'over the counter' N11 mufflers and pipes from the 1982 restoration. They sound much more aggressive (loud & raw) than the brand new Corvette Central N11's, which were installed on my 66 390hp car during restoration in 2010. No comparison at all.

[Joe L.]

Re: original sounding mufflers

Edward do you know how much of the exhaust pipe system had the double wall construction from the factory and if replacement exhaust pipe from GM parts counter were double wall construction like the factory installed?

Jim------


I have never verified this "double wall" exhaust pipe contention. If they were double wall, then they were certainly not double wall from end-to-end because if you look at the ends of the pipes, either the forward pipes or the rear pipes, there is absolutely no evidence of there being "two layers".

Also, the forward exhaust pipes for any given year were generally the same part number for either SERVICE or PRODUCTION. So, however the forward pipes were constructed, they were definitely the same for PRODUCTION or SERVICE.

[Michael G.]

Re: original sounding mufflers

I'm sure the N11 mufflers would work. But my question was did a BB Corvette sound like any other BB cars back when they were new

The mechanicals of the '67 427/390 are pretty much identical to that of the 396/360. The sounds of the exhaust systems of both cars would sound very much alike to their mechanical makeup.

[Terry M.]

Re: original sounding mufflers

Jim------


I have never verified this "double wall" exhaust pipe contention. If they were double wall, then they were certainly not double wall from end-to-end because if you look at the ends of the pipes, either the forward pipes or the rear pipes, there is absolutely no evidence of there being "two layers".

Also, the forward exhaust pipes for any given year were generally the same part number for either SERVICE or PRODUCTION. So, however the forward pipes were constructed, they were definitely the same for PRODUCTION or SERVICE.

I have verified the double wall on the early C3s FACTORY (front & rear) as well as the SERVICE front pipes. I ignore SERVICE rear pipes for other reasons. It wouldn't surprise me that C2s also had double wall exhaust pipes originally, but I will leave that official determination for others.

[Jack H.]

Re: original sounding mufflers

I've always been of the opinion that the location of the mufflers makes a big difference in the sound. The farther rearward the mufflers in relation to the pipes the better the sound IMHO. I've had Chevelles and Corvettes as my play cars, and IMHO, even stock low horsepower era small block C3 Corvettes with their rear mounted mufflers sound better than higher HP mid-to-late 60's and early 70's Chevelles with their mid span mufflers. Maybe its just me?

[Jeff S.]

Re: original sounding mufflers

Back in ancient times ('70s), I purchased two sets of counter/service replacement, midyear N-11 systems -- they were indeed of double-wall construction. I don't recall how the male & female joint was configured, however.

[John H.]

Re: original sounding mufflers

Chevrolet Engineering specs (for '67) say the rear pipes were "laminated", but not the fronts.