Ford 351/400
The 351 Cleveland and the 351/400M have similar heads with eight cover bolts, but they have different bellhousing patterns. The Cleveland shares a bellhousing pattern with the small-block Windsors (shown, on left), while the 351M/400 block (right) uses the larger pattern of the 429/460 big-blocks. Note the different spacing between the upper two sets of bolt holes (arrows)
Ford 351 Windsor
Ford made three different engines that carried a 351ci displacement, leading to a great deal of confusion. The popular 351 Windsor, which has six-bolt valve covers, is basically a raised-deck version of the 289/302 small-blocks. The taller deck surface is visible at the front and back of the block. These two ribs (arrows) at the back near the distributor clearly distinguish this as a 351 Windsor.
Ford 351 Cleveland
The 351 Clevelands and 351/400M engines have large, square heads with splayed valves and eight cover bolts. Cleveland heads are marked with a large numeral 2 or 4 in the upper corner of each head, signifying either a two- or four-barrel application. Produced only with two-barrel carbs, 351M/400 engines either have an "M" on each corner or no mark at all. The only way to tell a 351M from a 400 is by measuring the stroke. The 351M stroke is 3.50 inches; the 400M stroke is 4.00 inches.
Ford FE Series
The FE series of engines, produced in displacements of 332, 352, 360, 361, 390, 406, 410, 427, and 428 ci between 1958 and 1976, has a five-bolt valve cover and Chevy-style water pump and is also identifiable by its intake manifold, which forms part of the valve cover surface.
Cadillac
The torque-monster 472 and 500ci Cadillac motors share the same block casting number, so identification must be made by checking the crank stroke: The 500 has a 4.3-inch stroke; the 472's is 4.060 inches. With the pan off, crank ID is easy since only three casting numbers were used. All 472 cranks have a casting number ending in 424, which is cast on the edge of the third crank counterweight from the front. The 500s used cranks ending in either 094 or 793, which is cast on the side of the counterweight between the No. 3 and No. 4 crank throws. From '70 to '74, 500s came only in front-wheel-drive Eldorados; in '75 and '76, they were available in all the large models. CC