One of our own ‘bolters “Pre ‘68 Dave” is an expert on these Stovebolt engines and has a website that show the differences in the rockers and oil supply thru the years these engines were made.

Here is a link.

Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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