Buick Engine Identification, where to find the numbers

All "Nailheads" '57 - '66

225, 300, 340 For 215 V8:

The engine number is stamped on the engine forward of the right cylinder head.
The production code number is stamped upside down next to vehicle number.

For 300, 340 V8s:

The engine serial number is stamped on the left front face of the crankcase, just below the rocker arm cover. On cars equipped with power steering it will be necessary to remove the power steering pump bracket to view the complete number.
The production code number is stamped on the right side of the crankcase and can be viewed between the middle branches of the

For 198 V6:

The engine number is stamped on the engine forward of the right cylinder head.
The V6 engine production # is on the front of the block below the LH

For 225 V6:

The engine serial number is stamped on the left front face of the crankcase, just below the head gasket. On cars equipped with power steering it will be necessary to remove the power steering pump bracket to view the complete number.
The production code number can be found on the crankcase between the front and middle branches of the right exhaust manifold.

350 inch until 1971
The engine serial number is stamped on the front of the left cylinder bank. The production code number is between the left exhaust manifold and the two front spark plugs.

400 and 430 inch, 1967
The engine production code number is between the two forward branches of the right exhaust manifold, and the engine serial number is between the two rear branches.

L 250 inch from 1968
The engine serial number and the production code number are on the right side of the engine, to the rear of the distributor.

400, 430, 455 inch, 1968 on
The engine serial number is between the two front spark plugs and the left exhaust manifold, and the production code number is between the two rear plugs and the exhaust manifold, also on the left.

400, 430, 455 inch, all have the actual cubic inch that the block was cast for in the transmission mount saddle above the casting number.
In this case it is a 430.