Cut off date for Chambered Exhaust

[mockingbird812]

Does anyone have documentation or knowledge of when the c. exhaust could be ordered on a Camaro or Chevelle? http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

Thanks!

[bbbenny]

I know that the cutoff date, from a factory issued memo was may 19 th. 1969.BBBenny

[mockingbird812]

Thanks Benny. I had thot it was earlier in the year. Good info.

Thanks!

[DZ Fool]

Was it ever standard on early 69Z/28 's ( nov 68 )

[396L35]

[ QUOTE ]
Was it ever standard on early 69Z/28 's ( nov 68 )

[/ QUOTE ]
I dont know if it was standard on the early Z/28's but it was an option... I thought the cut off date was in April 69??? But this doesn't say that you couldn't get it over the counter at the parts dept.... Mark

[Mr70]

This should help.
From Technical Service Bulletin 69-T-8 dated April 15th,1969.
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"The sections of this bulletin that apply to Camaros with RPO Z/28 are being revised to include a letter design exhaust system.

Many of the early production 1969 Super Sport Chevelle and Camaro models were equipped with a chambered exhaust system.There are some local and State police Departments issuing warnings and citations to the owners of these vehicles for what they term "excessive noise".
Consequently,and effective in production on November 25th,1968,the Chambered exhaust system was discontinued as the standard exhaust system on Camaros w/options Z/28,L-34 and L-78,and also on Chevelles with options L-34,L-78 & L-89.
Since that time,the standard exhaust system on these vehicles has been the regular muffler dual exhaust as used w/RPO L-35,(325HP),except for the Camaro Z/28.This used the same regular muffler dual exhaust as option L-48,(300HP).
The chambered exhaust system is still available as optional equipment known as RPO NC8 in those area where this system is permissible.
The latest design system for Camaros with RPO Z/28 option includes resonators ahead of a modified deep tone muffler to further reduce the noise level.This system will be effective in production approximately April 15,1969.
On the basis of a customer request,Camaros w/RPO Z/28 option with the early built chambered,or the interim built regular muffler dual system,should be converted to the latest exhaust system w/resonators.The remaining options that used a chambered system should be converted to a regular muffler dual exhaust system.The parts required for conversion are listed on the following pages of this bulletin."
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It then goes on to show diagrams and part numbers to make these conversions at all Chevrolet dealerships on vehicles previously mentioned.

[mockingbird812]

Nice stuff Rick. Curious how they mention the applicability to "Z/28, L-34 and L-78" wrt Camaros and "L-34, L-78 & L-89" for Chevelles. Wonder why no reference to L-89 for Camaros? http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

Do you have the bulletin that Benny was referring to which does away with the NC8 option?

[Donnie]

(Do you have the bulletin that Benny was referring to which does away with the NC8 option?)

I do. I will snap a pic and send it to Bruce.

[mockingbird812]

Thanks Donnie! http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[Donnie]

heck, I can just send it to you Sam.

[mockingbird812]

that'll work. I can post it here too.

[email protected]

http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

[JChlupsa]

notice where the last paragraph states CAMARO SS's which a L89 would be

http://www.yenko.net/photos/data/500/69_Camaro_Bright_Metal_Exhausts_tips_for_dual_exha usts.JPG

[William]

L89 was not an engine option; it was an aluminum cylinder head option for L78; paperwork will show both options. Not necessary to list L89.

[Stefano]

My Copo Camaro's trim tag is dated O5D and the car was factory equipped with the NC8 option.

[mockingbird812]

[ QUOTE ]
L89 was not an engine option; it was an aluminum cylinder head option for L78; paperwork will show both options. Not necessary to list L89.

[/ QUOTE ]

Understand that. Look at Mr70s input on this thread were L89 is broken out separately for Chevelles (not Camaros).

Also, curious as to why the memo above was for Camaros only. Or would there have been a separate memo for Chevelles.

[mockingbird812]

Donnie provided this t-bulletin for me. Appears to be what Rick (Mr70) transcribed for us earlier. Thanks Donnie! http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

Second portion of bulletin is slow to load. Will f/u later. http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

http://img.photobucket.com/albums/v697/mockingbird812/DSCF0030_1.jpg

[mockingbird812]

Here's the rest of the t-bulletin....

http://img.photobucket.com/albums/v697/mockingbird812/DSCF0028_1-1.jpg

[Jeff H]

The bulletin seems to be saying that if a customer needed repairs or exhaust work or wanted the exhaust replaced that the dealer should change to the resonator/muffler setup. But it doesns't specifically state NC8 was no longer an available option.

[mockingbird812]

[ QUOTE ]
The bulletin seems to be saying that if a customer needed repairs or exhaust work or wanted the exhaust replaced that the dealer should change to the resonator/muffler setup. But it doesns't specifically state NC8 was no longer an available option.

[/ QUOTE ]

See the 6 May memo above. It cancels NC8 as an option, in Camaros anyway.

[Jeff H]

Interesting that the memo states "Camaro SS" and not Z28 and no mention of COPO. That might explain the 05D COPO with chambered exhaust. But the 05D COPO might have been ordered in early May with NC8 as well.

[Mark_C]

The memo states that NC8 was cancelled in all cars in production effective May 19th 1969. That means any car that didn't have the exhaust already attached to it at 8am on May 19th would get an RPO N10 dual exhaust system.

COPOs might be an exception but I would imagine that GM removed all the parts to make up a chambered exhaust from the assembly plants on 5/19 as well.