O.S. Cylinder Head FS-91S II & FS-91 II -P WITHOUT VALVES Cylinder Head Only for the OS Max FS 91 Surpass II Pumped Engine. The valve assembly is not included and if needed must be purchased separately. **Works with Surpass II Pumped and Non-Pumped** FEATURES Aluminum construction Pre-installed brass tubing guides for the valves INCLUDES One FS 91 Surpass Pumped Version One Aluminum Head Gasket COMMENTS For cylinder head with valves pre-installed, use OSMG5232. The intake manifold mount holes are diagonal across the throat (one at lower left and one at upper right