Cowl Induction on a 1966? [Archive] - Chevelle Tech

: Cowl Induction on a 1966?


Northwest29
May 18th, 08, 11:50 PM
Greetings all!

Over the weekend I was watching the Mecum auto auction and they showed a 1966 SS396 with cowl induction. The announcer went over it so quickly that I missed if he said that it was a 'factory' option, or after market. I had a 66 and never heard of this one. As far as I know 1970 was the first year of factory cowl induction for the Chevelles.

Can someone help me out here with the correct information?

Thanks in advance for your assistance.

cachevelle66
May 18th, 08, 11:55 PM
Cowl induction hood on anything earlier that a 70 Chevelle is aftermarket, most of the aftermarket cowl hoods are model after the Camaro dtyle, there was a air cleaner that was ducted to the cowl, it picked air though the cowl grille, upper/firewall cowl was cut for the duct.

Northwest29
May 19th, 08, 12:29 AM
Thanks cachevelle66 -

That's exactly what I saw, the air intake was from the pass side firewall and routed to the air cleaner - no special hood involved. I would assume you'd have to cut a hole in the firewall to make this guy work, an interesting mod for sure.

novaderrik
May 19th, 08, 2:15 AM
i don't think the plenum cowl induction setup was a factory installed option- but maybe it was available over the counter.
i do know, however, that an original piece is worth enough to put a decent down payment on a house around here, and repros cost way over $1000.
i also know that they just look badass, and GM engineers (along with people like Smokey Yunick) thought it was worth their time to develop and use it in NASCAR in the early 60's.

rianbechtold
May 19th, 08, 3:48 AM
That style cowl induction was a rare option for the early z28 camaros (may have only been the 67 year, I'm not sure). I have heard of people putting them on the early body chevelles but do not think/know that it was an option.

Does it work, well let's look at two pictures:

NASCAR engine bay in 1964:
http://images.hotrod.com/thehistoryof/113_0311_10z+1964_plymouth_petty+engine_view.jpg


NASCAR engine bay in 2007:
http://images.hotrod.com/techarticles/hrdp_0803_15_z+chevy_nascar_engine+.jpg

:thumbsup:

David Bates
May 19th, 08, 9:01 AM
That style cowl induction was a rare option for the early z28 camaros (may have only been the 67 year, I'm not sure). I have heard of people putting them on the early body chevelles but do not think/know that it was an option.

Not necessarily a RARE option. I've seen many full size BB equipped Chevy's with the cowl plenum air cleaner the most recent of which was a 1969 L72 4-Speed wagon at the Adirondack Nationals in Lake George NY.

Keith Tedford
May 19th, 08, 9:09 AM
This is what you are talking about? I think the repros are the other side of $2K if I'm not mistaken. It has been pointed out that the plastic piece that attaches to the cowl is not the same for Chevelle and Camaro. It is an attention getter if that's what you are after.

66 MYSTERY CHEVELLE
May 19th, 08, 10:24 AM
I have spoken to this subject matter many many times.. 66 Cowl Plenum Air Cleaners that is.. A SEARCH of this here at Team Chevelle will no doubt yield much info. worth the effort to search.

Over the counter High Performance item that was available for 66 SS and 67 SS and many other years and models of Chevelles and Camaros and Impalas... a Smokey Yunik concept...

Doubtful in my opinion that the Chateau Slate 66 SS from Oregon that went unsold at Mecum and BJ a couple years ago.. had a CP on it from day one... just my opinion.

That car is a 360 hp car and not that getting one was limited to the L-78 ( 375hp ) cars, but anyone that was looking to have this option back in 1966/1967 was likely racing and if they were, there were likely using an L-78 in 1966.. just my feeling.. still has a WOW factor!! Repros are very good.. about $2000 now... NOS.. about $5K

Not Factory installed.. cutting hole in firewall was not something the GM guys would have liked and still keep your warranty ;)

Again, do a search.. worth it!

Mike Crown

DZAUTO
May 19th, 08, 11:18 AM
Ron,
I think the answer to your question has been pretty well covered. And just to repeat, the correct term for pre-70 fresh air intake air cleaners is Cowl Plenum air cleaners (2yrs ago Chuck Hanson brought a 69 to CB07 with a CP air cleaner, supurb car!!!). The reason is because the air actually comes in from the vent area of the cowl just in front of and below the windshield. At one time, these air cleaners were available from Chev Parts Dept.
Factory installed??? That's always been debatable. But for sure, it was a part that you could buy from Chev. And for sure, the first time that it was available (and it WAS installed at the factory) as a genuine, installed part, was on the 1963 RPO Z11. The Z11 was the complete pkg (ONLY came one way) with a 427 (essentially a stroked 409), alum front sheet metal, bumpers, etc, 4sp, posi, no radio, heater and in a plain 2dr Impala ONLY (NON-SS) with dog dish hub caps.
The Z11 Impala actually arrived at the dealer with the Cowl Plenum air cleaner installed. It is also debatable as to how many of these Z11s were assembly line built (components were available from the parts dept). The numbers range between 47 and 57 cars actually built at the assembly plant. We may never know for sure the exact quantity. :D
There MAY be about 10-12 DOCUMENTED Z11s in existance today. One was recently discovered, bought and is presently undergoing restoration now.

Northwest29
May 19th, 08, 2:00 PM
This is what you are talking about? I think the repros are the other side of $2K if I'm not mistaken. It has been pointed out that the plastic piece that attaches to the cowl is not the same for Chevelle and Camaro. It is an attention getter if that's what you are after.


Hi Keith -

Thanks for the photo and inforamtion. That's the exact one that was shown on the Mecum auction. I wonder if it would be that much of a performance boost. But it does look cool.

Northwest29
May 19th, 08, 2:09 PM
I have spoken to this subject matter many many times.. 66 Cowl Plenum Air Cleaners that is.. A SEARCH of this here at Team Chevelle will no doubt yield much info. worth the effort to search.

Over the counter High Performance item that was available for 66 SS and 67 SS and many other years and models of Chevelles and Camaros and Impalas... a Smokey Yunik concept...

Doubtful in my opinion that the Chateau Slate 66 SS from Oregon that went unsold at Mecum and BJ a couple years ago.. had a CP on it from day one... just my opinion.

That car is a 360 hp car and not that getting one was limited to the L-78 ( 375hp ) cars, but anyone that was looking to have this option back in 1966/1967 was likely racing and if they were, there were likely using an L-78 in 1966.. just my feeling.. still has a WOW factor!! Repros are very good.. about $2000 now... NOS.. about $5K

Not Factory installed.. cutting hole in firewall was not something the GM guys would have liked and still keep your warranty ;)

Again, do a search.. worth it!

Mike Crown


Thanks Mike, I'll do a search and see what comes up. Holy cow, $2K!!! Now that's what I call a REAL profit margin. :D

Northwest29
May 19th, 08, 2:12 PM
Ron,
I think the answer to your question has been pretty well covered. And just to repeat, the correct term for pre-70 fresh air intake air cleaners is Cowl Plenum air cleaners (2yrs ago Chuck Hanson brought a 69 to CB07 with a CP air cleaner, suburb car!!!). The reason is because the air actually comes in from the vent area of the cowl just in front of and below the windshield. At one time, these air cleaners were available from Chev Parts Dept.
Factory installed??? That's always been debatable. But for sure, it was a part that you could buy from Chev. And for sure, the first time that it was available (and it WAS installed at the factory) as a genuine, installed part, was on the 1963 RPO Z11. The Z11 was the complete pkg (ONLY came one way) with a 427 (essentially a stroked 409), alum front sheet metal, bumpers, etc, 4sp, posi, no radio, heater and in a plain 2dr Impala ONLY (NON-SS) with dog dish hub caps.
The Z11 Impala actually arrived at the dealer with the Cowl Plenum air cleaner installed. It is also debatable as to how many of these Z11s were assembly line built (components were available from the parts dept). The numbers range between 47 and 57 cars actually built at the assembly plant. We may never know for sure the exact quantity. :D
There MAY be about 10-12 DOCUMENTED Z11s in existance today. One was recently discovered, bought and is presently undergoing restoration now.

Tom, I appreciate all the details. I sure never new all of that previously. Education is a wonderful thing. The correct term will help keep it straight and differentiated from the "Cowl" induction.


A Chevy fan in Mustang? Is that anything like a misnomer? (-:

DZAUTO
May 19th, 08, 3:14 PM
A Chevy fan in Mustang? Is that anything like a misnomer? (-:

Now do I seem like the kind of guy who would make fun of you if you got caught red handed with your pants down?

You're right, I would!!!! :D

(they've even had the Nat'l Mustang meet here in the past, acutally, it was quite impressive to see some of the ULTRA rare, early hi-po Mustangs)

DaleM
May 19th, 08, 3:42 PM
There was not a factory RPO code for the system, at least not reported by GM in their Accumulative Production/Final Model Year Reports for 1966 or 1967. It could have been listed as an 'Accessory' item along with such things as the litter containers, portable spot lights, etc. and installed at the dealership.

Keith Tedford
May 19th, 08, 4:57 PM
Does anyone know who reproduces the cowl plenum air cleaner setup?

L72Chevelle
May 19th, 08, 5:37 PM
Listed in Chevelle World is NKR Products out of Rutherford College, NC (828-874-2335) 6PM-9:30PM EST. Hope this helps, Phil.

Jerry70
May 19th, 08, 7:27 PM
I ran one on my `67 SS for awhile but it didn't make any difference in my times so I took it off. I was trapping about 109 which I suspect wasn't fast enough for it to have much effect. I had to special order it from the local Chevy dealer and I think it was about $85. The parts guys had never heard of one until I gave them a part number I'd gotten out of one of the "undergound" muscle car mags that were popular back then. When it came in all the parts staff and some of the techs came out to watch me open the carton :). One of the reasons I got rid of it was the cost of replacement filters. They were over $8 (about triple what a standard 14X3 cost at the time) and had to be special ordered also.

cheveezies
May 19th, 08, 11:26 PM
:) rookie question here ! . can't understand this one . a 66 cowl induction hood goe's for 450.00 , . you mean to say 1,500.00 is for the plastic induction piece to draw air down , through the hood grill's & into the air cleaner ? . i would think it include's the air cleaner & cover , which look's like it is custom cut at the rear to recieve the air induction piece .:confused:

DaleM
May 19th, 08, 11:50 PM
One really has nothing to do with the other. If you're referring to a 'cowl induction' hood being a simple rearward opening scooped hood, fresh air is drawn in from the rear of the scoop but there's no mechanism to direct it into the carburetor (except for the 70-72 Cowl Induction hoods), it's a hood and nothing more. The cowl plenum unit, on the other hand, is a sealed unit from the air intake to the carburetor and has nothing to do with a hood. In neither case is air drawn in from the grille area but rather from the base of the windshield.

66 MYSTERY CHEVELLE
May 20th, 08, 9:40 AM
:) rookie question here ! . can't understand this one . a 66 cowl induction hood goe's for 450.00 , . you mean to say 1,500.00 is for the plastic induction piece to draw air down , through the hood grill's & into the air cleaner ? . i would think it include's the air cleaner & cover , which look's like it is custom cut at the rear to recieve the air induction piece .:confused:


Tommy

You are thinking in terms of Racing.. reality .. most guys buying an NOS CP or Repro one are not buying it for that reason.. they are buying it for a different reason.. it's called the WOW Factor!! and it's not for the timid at heart or the light in the wallet guy.. These are put on cars that are known to have originally had one back in the day or for cars that are fully restored for show purposes... many can't understand why one would pay so much for an item like this... I can and I do. It's all about the WOW Factor.. trust me! :yes:

MarkM
May 21st, 08, 7:41 AM
I made my own. Obviously not going for the original look

http://www.fquick.com/images/vehicles/full/20166150254.jpg?1211370019

novaderrik
May 22nd, 08, 4:52 AM
I made my own. Obviously not going for the original look

http://www.fquick.com/images/vehicles/full/20166150254.jpg?1211370019

that looks stock- and pretty killer coupled with the ultra rare triple master cylinder option.

davewho1
May 22nd, 08, 6:07 AM
that looks stock- and pretty killer coupled with the ultra rare triple master cylinder option.

:D

jaf6738
May 22nd, 08, 7:19 AM
Here is some info I posted from an old thread:

Nelson Rudisill at NKR products is still making them special order. I talked to him earlier this year as, a better breathing system for my 67 is needed, and his custom system is still an option. I was reasearching thease and found the 7 page article from the old NCOA mag. I think this is some good reading for anyone intrested in this sort of system.
Attached Thumbnailshttp://www.chevelles.com/forums/attachment.php?attachmentid=12199&stc=1&thumb=1&d=1202772423 (http://www.chevelles.com/forums/attachment.php?attachmentid=12199&d=1202772423) http://www.chevelles.com/forums/attachment.php?attachmentid=12200&stc=1&thumb=1&d=1202772551 (http://www.chevelles.com/forums/attachment.php?attachmentid=12200&d=1202772551) http://www.chevelles.com/forums/attachment.php?attachmentid=12201&stc=1&thumb=1&d=1202772571 (http://www.chevelles.com/forums/attachment.php?attachmentid=12201&d=1202772571) http://www.chevelles.com/forums/attachment.php?attachmentid=12202&stc=1&thumb=1&d=1202772606 (http://www.chevelles.com/forums/attachment.php?attachmentid=12202&d=1202772606)

66 MYSTERY CHEVELLE
May 22nd, 08, 8:47 AM
http://webpages.charter.net/nelsonrudisill/nkrproducts/index.htm

Above is a direct LINK to Nelson's CP units.. check it out.... I still say, if you are looking for one of these... this is the way to go!!

Mike Crown

MarkM
May 22nd, 08, 8:57 AM
that looks stock- and pretty killer coupled with the ultra rare triple master cylinder option.


Yeah, it was a Smokey Yunick option. LOL

cuisinartvette
May 22nd, 08, 9:54 AM
MarkM that looks awesome man! What to do about the engine torquing over though?

Wish I could fab stuff like that. :beers:

rocks66ss
May 22nd, 08, 10:26 AM
What to do about the engine torquing over though?

That just gives you an opportunity to hone your welding skills every weekend ;)


Rocky

MarkM
May 22nd, 08, 11:48 AM
MarkM that looks awesome man! What to do about the engine torquing over though?

Wish I could fab stuff like that. :beers:

I'm not done with it yet. I'll have a rubber seal where the plenum meets the firewall.

I'm also running solid engine mounts.

MarkM
Jun 5th, 08, 4:47 PM
oppps. wrong thread.

madmetal66
May 31st, 09, 8:02 PM
Hi guys Iam new and have a few things to share. About 20 years ago I bought a 66 SS out of hemmings advirtised as a dealer installed 427/425 4 speed it had a 942 block 858 heads and 069 intake all right for 1966 but I didnt really believe it was a dealer install and didnt care. One thing that I thought was strange about the car when I got it was it had a plate covering a very poorly cut hole in the upper pass side fire wall. At the time i had no real knowlege of any cowl induction on anything other than a 1970. Then I found a book with this picture in it.http://<a href=http://s711.photobucket.com/albums/ww119/madmetal66/?action=view&current=scan0001.jpg target=_blank>http://i711.photobucket.com/albums/ww119/madmetal66/th_scan0001.jpg what do you guys think?

madmetal66
Jun 4th, 09, 10:40 PM
Hi guys .http://i711.photobucket.com/albums/ww119/madmetal66/th_scan0001.jpg (http://s711.photobucket.com/albums/ww119/madmetal66/?action=view&current=scan0001.jpg)Back bought 138 66 out of HEMMINGS the ad read
1966 Chevelle dealer installed 427/425 4 speed 12 bolt
Well I bought it 6500 bucks.. I was 20 years old at the time and all I knew was that the 1966 SuperSport was the only car Id ever want. This thing ran like a raped ape Id pass everything cept a gas station and a speed shop for octane boost or a dose of VP. Time went by and I took the body off and started to check this car out. What I found was 942 block 858 heads 069 intake and a plate screwed over the r/h cowl area. Well when I took that plate off I found a hole that looked like a rotten tooth beaver had made,and I fixed it. I thought WTF is this. Well a few years later I found this in book. Do any of you guys know anything at all about how I can conferm if this is what I have? The car was put on hold for many years now Iam finishing it. Reguardless of what it is, Iam making this cowl induction set up for it from alum
along with Alum fenders hood and bumper Now look at this if you havent already.