The 12 Valve War Head produced by Hamilton Cams is quickly becoming the go-to cylinder head for 12v Cummins performance engines. With excellent low-lift numbers as-cast, this is by far the best as-cast performance head on the market. Although the War Head is wet meaning it has coolant jackets, it is a competition cylinder head featuring a thicker deck, thicker port walls, taller casting and optimized port shapes so it does not have the restrictive factory high-swirl port design for lower-powered street use. If you take the War Head to the extreme by filling the water jackets, more porting, and machining the seats for larger valves, this head becomes arguably the best Cummins performance cylinder head available.
These heads come standard with 8mm valve guides, 1.75″ 45* exhaust valve seats, and 1.85″ 30* intake valve seats. Unfortunately, 8mm valves are not available in the length and size for this head so the guides must be opened up to 11/32″ to run the valves we offer. If you buy a complete head, we will perform the valve guide changes for you. If you buy a bare head, be sure to plan on valve guide work.
If you plan to run a 5.9 Cummins bore size approx 4.015″, 1.85″ is the largest intake valve that will safely clear the cylinder walls. If you run a 6.7 Cummins bore size approx 4.210″, a 1.97″ to 2″ intake valve fits great and is the size we recommend. If you’re playing with a solid block and a monster 4.400″ bore size, a 2.250″ intake valve works well with the War Head.
Due to the 0.400″ thicker casting, the War Head requires longer valves, longer head studs, and longer pushrods. It comes prepped for a side-draft intake or runner-type intake manifold so pick your favorite style and plan on drilling/tapping the head to receive your intake setup.