C1 & C2 Corvettes General C1 Corvette & C2 Corvette Discussion, Technical Info, Performance Upgrades, Project Builds, Restorations

Replaced my original N11 mufflers with new.

Thread Tools
 
Search this Thread
 
Old 12-07-2018, 12:34 AM
  #1  
mjdart
Burning Brakes
Thread Starter
 
mjdart's Avatar
 
Member Since: Sep 2000
Location: Coral Springs Florida
Posts: 762
Received 286 Likes on 161 Posts

Default Replaced my original N11 mufflers with new.

My '64 Sting Ray Coupe with L76 was ordered with the N11 off road exhaust. They finally developed rust holes as mufflers always used to. I decided to replace them with the best reproduction mufflers, I could find. After research I found Corvette Central exclusively carries the N11 exhaust with the GM License as Restoration Parts. Out of the box they looked very good, but how they fit and sound is also very important. I got the car up on jack stands and went about removing the old system. The mufflers come welded on to what I used to hear called intermediate pipes, that slip over the pipes that bolt up to the exhaust manifold. Now those pipes still looked perfect so I decided not to replace them. I also ordered 2 new donut gaskets as you need to remove the front pipes to easily install the new rear pipe and muffler assembly. From start to finish took about 3 1/2 hours to lift car, remove old system, install new, and lower car. Very pleased with the result and for $399 not a bad value. The engine is a stock L76 327 solid lifter engine. Here's a short video so you can hear the nice tone.




Finished installation on 1964 Sting Ray


Screen capture from YouTube video produced by Waldron's telling how the mufflers were developed. Search YouTube and you'll easily find it.

The following 3 users liked this post by mjdart:
Factoid (12-07-2018), ptjsk (12-08-2018), southsidestingray (10-20-2021)
Old 12-07-2018, 08:36 AM
  #2  
USMC 0802
Drifting

Support Corvetteforum!
 
USMC 0802's Avatar
 
Member Since: Jan 2016
Location: CENTCOM, Tampa, FL
Posts: 1,673
Received 959 Likes on 490 Posts
USMC
Default

Sounds great. I got the CC MagnaFlow system for my ‘66 and you can’t beat the price.

Car looks awesome - enjoy!
Old 12-07-2018, 09:09 AM
  #3  
Factoid
Le Mans Master

 
Factoid's Avatar
 
Member Since: Jul 2018
Location: San Antonio, TX/Mahopac, NY
Posts: 8,353
Received 5,524 Likes on 2,784 Posts
2024 Corvette of the Year Finalist - Modified
2024 Corvette of the Year Finalist - Unmodified
2023 C7 of the Year Winner - Modified
Default

Well done! My ‘64 coupe originally came with the N11 option. Now it has capped cutouts just below the manifolds. What is the difference between the stock exhaust and the N11? Is it simply different mufflers?

On a separate point, looking at how clean the rear of your car is and the relationship between the spare tire tub and rear crossmember, I realize just how twisted my rear crossmember is and that I need to replace it.

Thanks for posting and nice job on the install!
Old 12-07-2018, 09:33 AM
  #4  
Chuck Gongloff
Race Director
Support Corvetteforum!
 
Chuck Gongloff's Avatar
 
Member Since: Apr 1999
Location: Beverly Hills/Pine Ridge Florida
Posts: 10,733
Received 561 Likes on 349 Posts

Default

Originally Posted by Factoid
Well done! My ‘64 coupe originally came with the N11 option.

What is the difference between the stock exhaust and the N11? Is it simply different mufflers?

Thanks for posting and nice job on the install!
I think that the only difference between the "stock" muffler and the N11 muffler is one internal baffle.. The N11's have one baffle less..

That's a very nice system.. Nice install too .


Old 12-07-2018, 09:49 AM
  #5  
Bluestripe67
Race Director
Support Corvetteforum!
 
Bluestripe67's Avatar
 
Member Since: Jan 2002
Location: Close to DC
Posts: 14,535
Received 2,126 Likes on 1,465 Posts
C2 of the Year Finalist - Modified 2020

Default

Nice work, looks good and sounds healthy. Dennis
Old 12-07-2018, 10:05 AM
  #6  
mjdart
Burning Brakes
Thread Starter
 
mjdart's Avatar
 
Member Since: Sep 2000
Location: Coral Springs Florida
Posts: 762
Received 286 Likes on 161 Posts

Default

Originally Posted by Factoid
Well done! My ‘64 coupe originally came with the N11 option. Now it has capped cutouts just below the manifolds. What is the difference between the stock exhaust and the N11? Is it simply different mufflers?

On a separate point, looking at how clean the rear of your car is and the relationship between the spare tire tub and rear crossmember, I realize just how twisted my rear crossmember is and that I need to replace it.

Thanks for posting and nice job on the install!
I've read the N11 mufflers have one less baffle inside so less restriction and a deeper exhaust tone. The thing is without lookin inside using a borescope you really aren't sure. With the developing holes in my mufflers I couldn't tell from the sound as not all the exhaust gases weren't coming out the tip.
Old 12-07-2018, 10:11 AM
  #7  
mjdart
Burning Brakes
Thread Starter
 
mjdart's Avatar
 
Member Since: Sep 2000
Location: Coral Springs Florida
Posts: 762
Received 286 Likes on 161 Posts

Default

Originally Posted by Chuck Gongloff
I think that the only difference between the "stock" muffler and the N11 muffler is one internal baffle.. The N11's have one baffle less..

That's a very nice system.. Nice install too .
Thanks, I was impressed how the engineers set up the exhaust system giving you to points to adjust the muffler position to get the chrome exhaust tip centered perfectly in the rear hole in the body. Also the clamps between the front exhaust pipe and the intermediate pipe not only clamp tight preventing leaks but they are also used to center the exhaust pipes as they pass through the frame. They hang on the rear transmission bracket which has two wings to accomplish this. I call this elegant engineering, meaning simple, efficient and cost effective. It also allows the end user the ability to take it apart and reassemble without screwing it up!

Last edited by mjdart; 12-07-2018 at 10:13 AM.
The following users liked this post:
Chuck Gongloff (12-07-2018)
Old 12-07-2018, 10:13 AM
  #8  
68hemi
Race Director
 
68hemi's Avatar
 
Member Since: Nov 2003
Location: Cottonwood AZ
Posts: 10,698
Received 3,048 Likes on 1,934 Posts
C1 of Year Finalist (performance mods) 2019

Default

I have the N11 mufflers on my 1957 since I never put the top up on the car but on my 1965 I have the quieter stock mufflers so I can listen to the radio better. The N11’s do sound nice on your beautiful car.
The following users liked this post:
mjdart (12-07-2018)
Old 12-07-2018, 10:25 AM
  #9  
mjdart
Burning Brakes
Thread Starter
 
mjdart's Avatar
 
Member Since: Sep 2000
Location: Coral Springs Florida
Posts: 762
Received 286 Likes on 161 Posts

Default

Originally Posted by Factoid
Well done! My ‘64 coupe originally came with the N11 option. Now it has capped cutouts just below the manifolds. What is the difference between the stock exhaust and the N11? Is it simply different mufflers?

On a separate point, looking at how clean the rear of your car is and the relationship between the spare tire tub and rear crossmember, I realize just how twisted my rear crossmember is and that I need to replace it.

Thanks for posting and nice job on the install!
Thanks, I too was impressed by how straight everything was underneath. I recently installed a new, but original style (9) leaf spring manufactured by Eaton Corporation for Duntov Motor Company, so I got a very good look around doing that. I'll write up that experience in the future (4 1/2 hr. job). The old spring was weak and noisy as it rebounded from bumps.
What really amazed me was when I opened the spare tire carrier to remove it for access (another easy job) that it contained an ancient, but perfect, original looking spare Goodyear Tire (without any air in it). I pumped it up after wiping it down with rubber protectant and it seems fine, I've had the car about 3 years if anyone is wondering.

Last edited by mjdart; 12-07-2018 at 10:27 AM.
Old 12-07-2018, 11:10 AM
  #10  
DansYellow66
Race Director
Support Corvetteforum!
 
DansYellow66's Avatar
 
Member Since: Jan 2003
Location: Central Arkansas
Posts: 15,746
Received 2,618 Likes on 1,950 Posts

Default

Looks nice and sounds great. I wonder if any members have tried using band clamps on pipe connections in lieu of crush clamps. It would seem to make disassembly a lot easier if it has to be taken apart to pull a transmission or to remove the mufflers to get to the antenna or something. I have them on the undercar exhaust on my ERA Cobra and use a Walker sealer on the connections. They come apart with a little wiggling and pulling. I wish I had done so on my 67 GTX as working around the exhaust and H-pipe to pull the transmission was a pain.
Old 12-07-2018, 12:50 PM
  #11  
mjdart
Burning Brakes
Thread Starter
 
mjdart's Avatar
 
Member Since: Sep 2000
Location: Coral Springs Florida
Posts: 762
Received 286 Likes on 161 Posts

Default

Originally Posted by DansYellow66
Looks nice and sounds great. I wonder if any members have tried using band clamps on pipe connections in lieu of crush clamps. It would seem to make disassembly a lot easier if it has to be taken apart to pull a transmission or to remove the mufflers to get to the antenna or something. I have them on the undercar exhaust on my ERA Cobra and use a Walker sealer on the connections. They come apart with a little wiggling and pulling. I wish I had done so on my 67 GTX as working around the exhaust and H-pipe to pull the transmission was a pain.
Funny you should mention the antenna, I found a NOS one about 2 years ago, but I found the muffler and its welded intermediate pipe would need to removed to install it.
Guess what I forgot to do when I installed the new components!!! Well, I guess it'll sit in the garage a while longer...lol
The following users liked this post:
marshal135 (12-18-2021)

Get notified of new replies

To Replaced my original N11 mufflers with new.




Quick Reply: Replaced my original N11 mufflers with new.



All times are GMT -4. The time now is 10:05 PM.