Fine reproductions of Knucklehead cylinder heads to replace your worn originals or to build your bespoke custom engine. They perfectly handle larger displacement engines but also work well as a high performance upgrade for 61 cui. and 74 cui. engines. These heads have the late style big port intake flanges, as original for 1940-47. Valve seats are hardened for the use of today’s unleaded fuels and sized for stock 1.750” Ø exhaust and larger 1.940” Ø intake valves, but not machined. They feature stock 18 mm spark plug threads and a stock head bolt pattern, however, the head bolt threads are changed to UNF 7/16”-20 so you can use more common Panhead/Shovelhead head bolts. Valve guides for S&S aluminum valve spring covers are included, but not installed.
- fits OHV models 1936-1947
- cast iron, black, painted
- nominal bore: 3-7/16 ”
- exhaust flanges G: Knucklehead
- head bolt pattern: Knucklehead
- intake manifold flanges: Knucklehead plumber type (1940-1947)
- oil supply: external
- plug threads: 1 x M18 x 1.5 x 12.7 mm
- with intake manifold nipples and valve guides
- replaces OEM 16700-40, and 16697-40
- USA

Have any questions?
Our service team will be glad to help out: Mondays - Thursdays 09:00-16:00 CET, Fridays 08:00-16:00 CET, Phone: +49 / 931 250 61 16, eMail: service@wwag.com