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**Steeveedee** · 03-13-2021, 11:19 PM

So, what is that "Z20 Engine Conversion" mean?

OK, I found the answer. Looks like the AIR equipment was left off and the holes in the head or manifolds were plugged! Wild! I've never heard of it coming from the factory like that, and I was a SMOG-licensed tech in California for many years.. I know plenty of people who did the plugs after the fact. I suspect that a run of engines that were "universal" as far as having the holes tapped in the heads for the AIR pipes needed the holes plugged later. Seems easier from a tooling standpoint. Plus, the SMOG stuff was changing rapidly in those days.

03-13-2021, 11:19 PM	#1237
Steeveedee Who Changed This? Join Date: Jan 2013 Location: Simi Valley, CA Posts: 10,155	Re: Post your 60-66 craigslist finds So, what is that "Z20 Engine Conversion" mean? OK, I found the answer. Looks like the AIR equipment was left off and the holes in the head or manifolds were plugged! Wild! I've never heard of it coming from the factory like that, and I was a SMOG-licensed tech in California for many years.. I know plenty of people who did the plugs after the fact. I suspect that a run of engines that were "universal" as far as having the holes tapped in the heads for the AIR pipes needed the holes plugged later. Seems easier from a tooling standpoint. Plus, the SMOG stuff was changing rapidly in those days. __________________ ~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA Last edited by Steeveedee; 03-13-2021 at 11:34 PM.