The 1953-1955 235 cubic inch engines in Corvettes were only matched with a 2-speed PowerGlide transmission. Since many parts on these early 'Vettes were from Chevy autos, and since the Chevy auto 235 with PowerGlide had hydraulic lifters, one might guess that the lifters were hydraulic,
However, the "Chevrolet Service News" of May & July 1954 gives Corvette 235 Valve Adjustment settings of 0.008" for Intake and 0.020" for Exhaust.
Was the 261 camshaft used in all the '53-'55 235 Covette engines; or, was the higher-lift 261 camshaft the mid-year change in the Corvette 235 that raised the horsepower from 150 to 155?
Tim
