Ford Performance Parts Boss 351 C.I.D. Engine Blocks

Ford Performance Parts Boss 351 c.i.d. engine blocks are based on Windsor 351 architecture with Cleveland-sized 2.749 in. main bearing journals. Available in two deck heights, 9.2 in. and 9.5 in., they feature 4-bolt main caps and screw-in freeze plugs. Technological improvements, such as splayed main bolts, siamesed bores with engineered coolant cross-drilling, front crossover lifter oiling, and diesel-grade iron with 41,000 psi tensile strength separate Ford Performance Parts Boss 351 c.i.d. engine blocks from both stock and aftermarket blocks. They can accept a maximum stroke of up to 4.250 in., depending on the crankshaft/connecting rod manufacturer, with a maximum bore size topping out at 4.185 in. (sonic check recommended). Features include: * Available in standard and Big Bore versions * Supports displacements up to 460 cubic inches * Splayed 4-bolt main on 2, 3, 4, main caps * 2-bolt mains on 1 and 5 main caps * Main bearing bores finished to low limit * Finished lifter bores * Machined to accept factory roller lifter guides and lifter guide retainer * Revised cooling system passageways * Increased bulkhead material * Threaded core and galley plugs (straight thread port plugs with O-ring) * Requires special length 1/2 in. head bolts M-6065-BOSS or head studs M-6014-BOSS recommended with M-6049-X306/307/Z304DA heads * Designed for M-6049-X306//X307/C3/D3/Z304DA cylinder heads * Not designed for production 302/351W or M-6049-Y302/Y303/X302/X303/X304/X305 cylinder heads * Use common O.D. cam bearings M-6261-J351/R351 * Unique cam plug M-6026-S351 included * Compatible with original 302 and 351W blocks * Designed to use stock type timing cover (M-6059-D351 with fuel pump provision recommended) * Fits factory Mustang oil pan with custom oil pick-up tube M-6622-BOSS302 * Retains clutch cross shaft pivot hole * Original-style oil filter location * Original motor mount boss locations * Original bell housing pattern * 9.2 in. deck height blocks weigh approximately 195 lbs. * 9.5 in. deck height blocks weigh approximately 205 lbs. * Great price and value Show Less