The apparatus is all part of the total emissions control package. What I have observed is that manual use the A.I.R. Pump with no Thermac valve on the snorkel, while the automatic cars got the Thermac on the snorkel & no A.I.R.. So conventional wisdom suggests.... Except that in '68 I have seen documents for high-performance U.S.-sourced models (L78 Camaro SS396, L79 Nova) that listed "KD1 - A.I.R. System delete for General Motors Canada". KD1 eh? It would have come in handy when ordering a late Corvair.

Any 1969 Canadian Pontiacs I have seen followed the protocol for emissions equipment, e.g an L36 / M20 got the smog pump. Closed element air cleaner V8s (and sixes supposedly) with automatic transmissions used a Thermac & no smog pump.

For '70 the TCS replaced in almost all cases the smog pump. TCS "games" the emissions for the duration of the 10 - 20 second test then reverts to allow vacuum advance. How that is different from the VW Dieselgate I don't know.

 

-- Edited by CdnGMfan on Friday 17th of March 2023 02:53:41 PM

Info from a friend who owns an original 1969 Biscayne 427 4Spd.

 

"I have seen all 1968 427s with the full breather and all had the PCV hose,

side breather vent filter and exhaust tube to the exhaust manifold.

Very enclosed system but it made the emissions folks happy"

I have air cleaners just wondering which is correct. the auto or the 4 speed for canadian built cars. I've been told the auto air cleaner for all applications.

68 385 M40

blkl36 wrote:

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Question, does anyone have or had an original survivor 1968 385 hp Canadian built Chevrolet or pontiac who has pictures of or knows/remembers definitively which air cleaner was used? 

My car is a 1968 Biscayne and I have the recognized 4 speed air cleaner (no thermal heat stove) but since the 68's did not have A.I.R pumps like the american 4 speed counterpart, It has come up that perhaps the 4 speed Canadian built cars used the Auto trans air cleaner (the one with the thermal heat stove).I have seen some parts books that suggest this, but I want to be sure to have the correct air cleaner. My engine is a 3S. Also might be helpful to know if the 396 4 speed cars used the thermal air cleaner from stock as well.

thank you

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          My 68 SD396 w/L35 and M20 has a Thermac style oe air cleaner, I think all Canadian spec cars used the Thermac style air cleaner except the high-perf open element engines.

sure!

nice! thank you!

I believe the 1968 situation was unique with the "K81 - deletion" of the A.I.R. pump on manual & open-element air cleaner cars. Remember that in '67 there were no smog pumps in Canada even as an option. Back in '66 in California when smog pumps really started there was a 1-year exemption for the L78 smog, but for '67 they had to comply.
For 1969 GM Canada seemed to make their cars more aligned with the U.S., from lacquer paint to smog equipment. I believe this was likely due to sending much more Canadian production to the U.S. in order to offset the stuff coming into Canada from the U.S as per the Auto Pact.

I've seen a '69 Pontiac L36/M20 that had all the smog stuff a U.S engine would be dressed with. It was on a gold 2+2 that had sat since '76. Many here probably remember it years ago when it came up for sale.

Every gear-head hated those smog pumps and most were thrown away. Today with the smog police doing reconnaissance covertly at cruises, that old garbage is now worth gold if you want to keep your car on the road around these parts.