Speedmaster 1-286-005-01 Ford Windsor Billet Main Iron Engine Block - 351W 4-Bolt

The Speedmaster 1-286-005-01 is a high-performance cast iron engine block designed for Ford 351W Windsor applications. Engineered for serious street and race builds, this block features a 4.125" bore, accepts 351 Cleveland main bearings (M-351C), and has a 9.500" deck height. Built to handle extreme horsepower applications exceeding 1,500 HP, it's ideal for supercharged, turbocharged, and nitrous oxide builds.

Key Features:

• Premium cast iron construction using high-density iron with extra-thick cylinder walls and deck surfaces for maximum strength
• Billet steel 4-bolt main caps with splayed bolt pattern for superior crankshaft support under extreme loads
• Enhanced water jacket design with scalloped openings for improved coolant flow and thermal management
• Enlarged lifter bosses accommodate offset or oversize lifters for performance camshaft applications
• Reinforced webbing throughout the block provides exceptional rigidity and durability
• Stock external dimensions allow use of factory components and maintains OEM appearance

Specifications:

• Bore: 4.125 inches
• Deck Height: 9.500 inches
• Main Bearing: 351 Cleveland style
• Main Caps: 4-bolt billet steel with splayed configuration

Required Components:

• Cam Bearings: PCE236.1008, SBF-1T, or equivalent 32210041
• Rear Main Seal: Fel-Pro #2921 or #2942 (4.500" x 3.000")

This block eliminates common factory weaknesses while maintaining compatibility with standard Ford small block components, making it the perfect foundation for high-horsepower Windsor builds that demand reliability and strength.