Ford Windsor Forums

No, thats very wrong!

The 302 boss was a 4 bolt main 302 "windsor" block.  The block came from the "trans am" racing period.  Instead of the tunnel port heads, "cleveland" styled 4v heads were installed.  These heads had slightly smaller chambers than the 351 cleveland and featured coolant passages on the intake side of the head.  The Cleveland head featured HUGE canted valves, semi hemishperical chambers, and insanely large ports.  The 302 Boss also used domed pistons and rods from the 289".  A solid lifter camshaft was installed also.

The 302 uses 7/16" head bolts, and the 351w uses 1/2"headbolts.  I believe the 302 boss, 351c, 351m, and 400 all use 7/16" headbolts.  The 289, 302, 351w, 351c, 351m, and 400 all use the same headbolt pattern and heads can be exchanged from engine to engine with a "fair amount" of machine work.

Cleveland style engines do not have any coolant traveling through their intake manifolds.

My recommendation for building a "boss 302" is too purchase either CHI 2v head or "aussie" 2v cleveland heads.  Then have the buy Edelbrocks "e-boss 302" intake manifold.  Use a milling machine to cut the coolant passage in the intake manifold and plug off the old coolant passages in the bottome of the heads.  Put the heads on a 302 block with custom pistons.  351c 4v pistons would have plenty of valve clearance and are only slightly taller than 302 pistons, you may be able to shave the head of the piston and use those.