I know that my engine is a 62. But how do I tell if it is the High-Compression motor or not. Block # 582813. The only info that I was able to fine is that if it is painted red it is the high-compression and green is low. My block color is red and the air cleaner said high-compression, but we all know how that can change over the years. Any info would help.
If you got the heads off you could measure the area and find the compression ratio (hi comp olds is bout 11:1 i think) Factory #'s are 345 BHP and 440! ft/lbs
if I'm not mistaken it's the pistons that make the difference the lower 8.75 compession pistons were dished the higher 10.25 compression pistons were flat if your motor is in good running order you should see a difference in a compression test 185 for high and 150 for low both my '62 98's air cleaners said "ultra high compression" and had the 10.25 compression motors
make a probe out of a piece of coat hanger wire,then remove one of the spark plugs and poke around a little,you'll be able to feel if there's a dish in the top of the piston or not. BTW i think it's more like 8.25 or 8.5 compression,but i've seen different figures.
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