Here’s a closeup look inside the innovative Pontiac Tempest overhead-cam six in an original factory training film.

A few years ago here at Mac’s Motor City Garage, we ran a feature on Pontiac’s forward-leaning 1966 overhead-cam six (See “Inside the 1966 Pontiac OHC 6,” Nov. 12, 2020.) Now we’ve got another look at the engine from a different angle, courtesy of an original factory film (actually, an excerpt from a much longer production). Here we get some nice glimpses into the engine’s features and construction, including the timing  belt drive and combustion chambers.  And we also get to learn some of the reasoning behind the OHC six—including what the Pontiac folks considered its key selling points.

The OHC six, you may recall, was spun off from the Pontiac division’s earlier R&D work on overhead-cam V8s (see our feature here).  As the announcer explains, the design’s greater efficiencies could have been used to increase either economy or performance, and here Pontiac chose performance. In ’66 base form, the six developed 165 hp at 4700 rpm, nearly 20 percent more power than the equivalent Chevy 6. And though it’s not shown here, there was a four-barrel hi-po version with 207 hp, which was respectable performance for a small V8 in those days. Check out the video.