Cylinder Heads
The Northstar
cylinder heads are semi-permanent mold cast aluminum with powdered metal
valve seat inserts and
valve guides. Two 33 mm intake valves and two 29 mm exhaust valves are actuated by direct acting hydraulic lash adjusters. Separate intake and exhaust camshafts are supported by five bearings machined into the cylinder head with
camshaft thrust taken by the first bearing (the left hand intake cam has an additional bearing to accommodate the water pump drive). The combustion chamber is roughly in the shape of a clover leaf with a nominal volume of 51.8 cc and a centrally located
spark plug.