The neat thing about the 351W block is that you can push the displacement to 427 cubic inches, or even more in some cases. The down side is that it won't be a cheap shortblock. But, how about using an FE engine instead, maybe a 390 or a 427 or a 428? There were thousands of 390 inch engines produced by Ford between 1961 & 1971. Bore was 4.05" and the stroke was 3.78". The 427 was produced between 1963 & 1968, so there are less of them around. The bore and stroke for the 427 was 4.23" x 3.78". As you can see, the stroke on the 390 is the same as the 427. A small bore job on the 390 will allow you to get 427 cubic inches, and purchase stock Ford replacment pistons. The 428 was produced between 1966 and 1970. Bore and stroke was 4.13" x 3.98". Everything in the FE engines are mix and match. For instance, you can use the pistons from a 427, and a crank (and rods) from the 428, and wind up with 447 cubic inches.
It's a very easy swap, and yes, Long Tube headers are available for the FE in 1 3/4", 1 7/8" and 2" primaries...
It's a very easy swap, and yes, Long Tube headers are available for the FE in 1 3/4", 1 7/8" and 2" primaries...