Engine - Boss 302 - Bare Block - 4.115 in Bore - 8.200 Deck - 4-Bolt Main - 2-Piece Seal - Iron - Ford Cleveland / Modified - Each

Ford Racing BOSS 302 Cylinder Block Big Bore

In the world of racing and performance, BIGGER is always better. Ford Performance gets it - and that's why it offers BOSS small blocks in Big Bore versions. The Ford Performance BOSS blocks are designed to be a replacement for the legendary BOSS 302 and BOSS 351 blocks using the latest technology and manufacturing techniques available. Cast from diesel grade iron with siamese bores, thick cylinder walls and decks, BOSS block strength is far superior to any Ford production block ever offered. Ford Performance Big Bore version of the BOSS 302 block makes it simpler and more economical to build really BIG small blocks. To insure the most precise bore location, concentricity and integrity, the BOSS Big Bore blocks are machined an additional .125 in. during the initial block fixturing and boring stage. With an unfinished bore size of 4.120 in., Ford Performance BOSS 302 Big Bore blocks will support engine sizes up to 363 cubic inches. The Ford Performance BOSS block capability has been proven around the world, both on the track and on the street. And, all Ford Performance BOSS blocks are cast and machined to the highest industry standards in the USA. 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; Uses common OD cam bearings M-6261-J351/R351; Unique cam plug M-6026-S351 included; M-6051-S331 or M-6051-CP331 head gasket recommended; Designed to be compatible with the original 302 and 351W blocks. Designed to use stock type timing cover, timing Cover M-6059-D351 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; Weighs approximately 163 lbs.; The foundation for 8.2 in. deck projects

Additional Information

Boss Big Bore Engine Block; 302 cu. in.; 4.125 in. Bore Capacity Finished at 4.115 in. Rough Bore; Designed For Cyl. Heads M-6049-X306//X307/C3/D3/Z304DA;

Product Overview

In the world of racing and performance, BIGGER is always better. Ford Performance gets it - and that's why it offers BOSS small blocks in Big Bore versions. The Ford Performance BOSS blocks are designed to be a replacement for the legendary BOSS 302 and BOSS 351 blocks using the latest technology and manufacturing techniques available. Cast from diesel grade iron with siamese bores, thick cylinder walls and decks, BOSS block strength is far superior to any Ford production block ever offered. Ford Performance Big Bore version of the BOSS 302 block makes it simpler and more economical to build really BIG small blocks. To insure the most precise bore location, concentricity and integrity, the BOSS Big Bore blocks are machined an additional .125 in. during the initial block fixturing and boring stage. With an unfinished bore size of 4.120 in., Ford Performance BOSS 302 Big Bore blocks will support engine sizes up to 363 cubic inches. The Ford Performance BOSS block capability has been proven around the world, both on the track and on the street. And, all Ford Performance BOSS blocks are cast and machined to the highest industry standards in the USA. 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; Uses common OD cam bearings M-6261-J351/R351; Unique cam plug M-6026-S351 included; M-6051-S331 or M-6051-CP331 head gasket recommended; Designed to be compatible with the original 302 and 351W blocks. Designed to use stock type timing cover, timing Cover M-6059-D351 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; Weighs approximately 163 lbs.; The foundation for 8.2 in. deck projects

• Requires Head Gaskets M-6051-CP331 or M-6051-S331

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Product Details

Product Downloads

#	Document Type	Download
1.	Installation Instructions

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Reference Information

Cylinder Block, Boss 302, 8.200 in. Deck, 4.115 in. Rough Bore, Each

The perfect foundation for your Boss engine--Ford Performance Parts Boss 302 engine blocks! They're built stronger than the originals to make your high performance build a success. Designed as replacements for the legendary Boss 302 and Boss 351 blocks, they use the latest technology and manufacturing techniques. Cast from diesel-grade iron with siamesed bores, thick cylinder walls and decks, Boss block strength is far superior to any Ford production block. Boss 302 blocks are available in standard and Big Bore versions that support engine sizes up to 363 c.i.d. Proven around the world, both on the track and on the street; all Ford Performance Boss 302 blocks are cast and machined to the highest industry standards in the USA.

Features include:
• Big Bore version features 4.125 in. bore capacity, finished at 4.115 in. rough bore
• Standard bore version is finished at 3.990 to 3.995 in. rough bore with 4.125 in. bore capacity
• 8.2 in. deck height, finished at 8.200 in. plus .010 to .015 in.
• Optimized cylinder wall length for stroker applications up to 3.5 in. with no grinding or clearancing (depends on crank/rod manufacturer)
• Splayed 4-bolt mains on 2, 3, 4, main caps
• 2-bolt main on first and fifth main caps
• Main bearing bores finished to low limit
• Finished lifter bores
• Machined to accept factory roller lifter guides and lifter guide retainer
• Fits factory 1979-95 Mustang oil pan with custom oil pickup tube, part number: M-6622-BOSS302
• NASCAR inspired front oil feed on both lifter galleys
• Revised cooling system passageways
• Increased bulkhead material
• Threaded core and galley plugs (straight thread port plugs with O-ring)
• Require 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
• Uses common O.D. cam bearings M-6261-J351/R351
• Unique cam plug M-6026-S351 included
• M-6051-S331 or M-6051-CP331 head gasket recommended
• Uses stock-type timing cover (M-6059-D351 recommended; includes fuel pump provision)
• Retains clutch cross shaft pivot hole
• Original-style oil filter location
• Original motor mount boss locations
• Original bell housing pattern
• Approximate weights: Big Bore 163 lbs.; standard bore 175 lbs.