Manifold Pre-Heat tube MISSING!!!! (Oh My Gosh!!)

[Spidey7]

Hey Y'all, the engine on my 1969 RS/SS Pace car seems to have an option called "Pre-Heat". It's a tube that runs from the Air-cleaner snout back down into the manifold to feed it heated air. The only mention I can find about this is on Z-28's of that year (And possibly Pace cars). Does anyone know if it belongs there? And if it does, I can't find one ANYWHERE! There don't appear to be any reproductions being made (Which is amazing considering the fact that Year One and Ricks make every sticker and bolt and screw that you can find on that car.) Should I put it back? And if so then where the heck can I find a new manifold "Pre-Heat Tube". Thanks heap-loads fellow brethren!

[Gramps69Z]

Make sure your exhaust manifold, and air cleaner has the place for one.  They were installed on a lot of cars and you should be able to find one at your local junk yard.  I believe it was on the passenger side.

[Spidey7]

Yeah, There is the spot for one on both the air-cleaner and the manifold, but I was led to believe that the tube could only be found on Z-28's. You're saying that it is a relatively common part? Do you know if anyone does a repro? There really aren't any junk yards in my area that hold anything older than the mid to late 80's. Thanks for your help. 

[Gramps69Z]

This tube was installed on most cars not only Camaro's.  You may be able to get one from a parts store, or dealer.  Do a search online and see what comes up.

[rich69rs]

Hey Y'all, the engine on my 1969 RS/SS Pace car seems to have an option called "Pre-Heat". It's a tube that runs from the Air-cleaner snout back down into the manifold to feed it heated air.

http://www.camaros.org/emissions.shtml
The Controlled Combustion System (CCS) was introduced in 1968 and was used on cars that did not receive the AIR system (automatic transmissions). CCS improved combustion efficiency via recalibrated carburetor and distributor settings and higher operating temperatures (compared to 1967). The higher operating temperatures were accomplished by using a 195°F coolant thermostat (instead of 180°F) and the use of a thermostatically controlled air cleaner (ThermAC). The ThermAC system was designed to warm intake air to 100°F when underhood temperatures were less than 100°F. It consisted of a damper door mounted on the snorkel of the air cleaner which directed warm air from a heat stove on the exhaust manifold into the air cleaner.

http://www.camaros.org/forum/index.php?topic=1032.msg5591#msg5591

Exhaust Manifold Part Numbers for 1969 Camaro 327/210 hp, 307/200 hp, or 350/250, 255, 300 hp engines w/auto transmission and no A.I.R.
LH side p/n:  3942529
RH side p/n:  3932376
These manifolds were also used in 1969 on Chevelle and Chevy II 307 and 350 engines with auto tranny and no A.I.R. 

Exhaust Manifold Part Numbers for 1969 Camaro for all manual transmission, with A.I.R., small block Camaro applications for 1969 including the 302 Z28 engine.  These manifolds have drilled and tapped connections for A.I.R.
LH 3942527
RH 3946826

In 1969 Camaro SB applications, there is a distinct difference in the RH manifolds between a standard transmission ("826" manifold) and an auto transmission ("376" manifold).   The "376" manifold incorporates a heat stove, is wider, with the heat stove riveted to it.  (The "826" manifold for standard transmission cars does not have the heat stove, since the Thermac / heat stove was an emmission system only applicable to an auto tran setup.)

I saw on one of these heat stove tubes last Sat. at a local junk yard - it was on an early '70's Chevy pick up truck.  Appeared to be identical to the one shown in the pic.  Thought about buying it, but didn't.

[KevinW]

Spidey, Those tube came on a lot of cars except for the Z/28 since Zs are only 4 speeds, they did not use the auto manifolds.  The tubes came in a couple of different sizes based on air cleaner and carb.  Your pace car with a cowl hood needs one that is different than a 2bbl 327 engine with the small air cleaner.  Keep looking on ebay (they come up occassionally as part of an air cleaner) like this one http://cgi.ebay.com/ebaymotors/CAMARO-CHEVELLE-NOVA-4-BARREL-AIR-CLEANER-ASSEMBLY_W0QQitemZ150188454002QQihZ005QQcategoryZ6763QQssPageNameZWDVWQQrdZ1QQcmdZViewItem or put a want ad up on Team Camaro.

[Spidey7]

Thanks all for the great info. That's really helpful!!!! It's funny that I thought that it was only available for the Z-28 and it turns out that is the only model it's not available on. Thanks KevinW for taking the time to find that auction for me. I'll keep looking for one.

[169INDY]

Lets see if I can post a pic of my 350/300 th-350 w/ cowl induction Air cleaner with thermo updraft tube.

http://www.yenko.net/photos/data/500/medium/Thermo_pipe.jpg

 

[Spidey7]

I GOT MY MANIFOLD PRE-HEAT TUBE!!!!!! I won the eBay auction. Thanks to everyone who helped. Especially you rich69rs for fingding the auction for me. Thanks again. You're all a swell bunch of guys.

[Spidey7]

Damnit!!! I got the air-cleaner assembly in (It's beautiful by the way) and the thing doesn't fit. It mounts fine, but the height of the pan is too short to reach the underside of the hood in order to work with the cowl induction. The air assembly is the same one that works with the Nova, and the Chevelle. So now I'm wondering if maybe there was a "Special" air-assembly that was made to work specifically with the "Super Scoop" hood as opposed to the general one that worked with all three models. Anyone know anything? (Or need an Air-Cleaner assembly? )
 

[tom]

I beleive there were two different cleaners, a big block, and a small block version. sounds like you got the wrong one.

Tom

[JohnZ]

There were THREE different air cleaners for ZL2 - one for L-48 manuals (snout with no vacuum valve), one for L-48 automatics (snout with vacuum valve for tube), and one for Z/28 and big-blocks (snout with no vacuum valve). In addition, there were two extension rings that went between the top of the air cleaner base and the flange that carried the rubber seal to the hood - one for L-48, and one for Z/28 (big-blocks didn't use an extension ring). The L-48 automatic was the only combination that used the snout with the vacuum valve and the heat tube from the exhaust manifold. All parts are shown in the ZL2 section of the assembly manual.

[KevinW]

Spidey, you need the SS350 extension ring that fits in between the air cleaner base and seal ring.  Available repro!

[Gramps69Z]

You'll need the seal for the ring.