2 bolt or 4 bolt main in a 74 L48 engine
The L48s had the narrow, six inch balancer and the L82s had the thick, eight inch one. I think that hold across the board for most high performance and special high performance small blocks.
Ok back to the topic at hand any way to figure out if it is 2 or 4 bolt main from the serial number off the front passenger side of the engine block? Well my serial number is 1z1775352 (i think a little hard to see)
The stamped in engine number won't tell you if it's two or four, only that the engine was originally installed in a particular model with the tranny type and in our case if it's a L48 or L82. Are you just curious as to what you have or are you planning on building the motor up? A two bolt bottom end can stand up to 500 hp if everything is in proper order.


