Once upon an Oldsmobile ad campaign

10.5 to 1 compression was advertised as Ultra-High-Compression!


Type -- Ultra-High-Compression V-8
Horsepower -- 345 @ 4600
R.P.M.Torque -- 440 lb.-ft. @ 2800
R.P.M.Displacement -- 394 cubic inches
Bore -- 4 1/8"Stroke -- 3 11/16"
Compression Ratio -- 10.5 to 1

Sorry about the poor resolution of the photo.

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