Ford Performance Engine Block Boss 351W 4.125" Bore 9.2" Deck Height M-6010-BOSS35192

If you're building a serious small-block 351W engine, you need a block engineered to handle real power without compromise. The Ford Performance Boss 351W delivers diesel-grade iron construction with reinforced critical areas, giving you the material strength required for high-boost, high-RPM competition applications. With a 4.125-inch bore and support for up to a 4.00-inch stroke, this block provides the displacement and durability foundation that separates amateur builds from championship engines.

This block is purpose-built for dedicated performance heads and demands precision machine work. Expect superior oiling and cooling performance through revised passageways and a siamese bore design, while the splayed 4-bolt main caps on positions 2, 3, and 4 ensure crankshaft stability under extreme loads. The finished lifter bores and threaded galley plugs eliminate common weak points found in stock castings.

Competition use only—not street legal.

• Bore capacity: 4.125"
• Deck height: 9.2"
• Max stroke: 4.00"
• Main journal: 2.749"
• Material: Diesel-grade iron
• Main caps: Splayed 4-bolt (2-4)
• Main caps: 2-bolt (1, 5)
• Lifter bores: Finished
• Galley plugs: Threaded O-ring
• Head bolt: Special length required
• Compatible heads: X306, X307, X2, C3, D3, Z304DA, Z2
• Incompatible: 302/351W production heads
• Recommended gasket: M-6051-S331 or CP331
• Weight: ~195 lbs