System Specifications

Cylinder head flatness 25 microns
Cylinder head gasket surface finish 10 microns
Combustion chamber volume 53 ± .5 cc (3.2342 ± 0.0305 ci)
Valve arrangement (front to rear) LH EIEIEIEI
Valve arrangement (front to rear) RH IEIEIEIE
Valve guide bore diameter 7.044 - 7.015 mm (0.2773 - 0.2762 inch)
Valve stem diameter (intake) 6.995 - 6.975 mm (0.2753 - 0.2746 inch)
Valve stem diameter (exhaust) 6.970 - 6.949 mm (0.2744 - 0.2735 inch)
Valve stem-to-guide clearance (intake) 0.069 - 0.020 mm (0.0027 - 0.0007 inch)
Valve stem-to-guide clearance (exhaust) 0.095 - 0.046 mm (0.0037 - 0.0018 inch)
Valve head diameter (intake) 44.5 mm (1.7519 inch)
Valve head diameter (exhaust) 34.0 mm (1.3385 inch)
Valve face runout limit 0.05 mm (0.0019)
Valve face angle 45.5 degrees
Valve seat width (intake) 2.1 - 1.9 mm (0.0827 - 0.0748 inch)
Valve seat width (exhaust) 2.1 - 1.9 mm (0.0827 - 0.0748 inch)
Valve seat runout (TIR) 0.025 mm (0.0009 inch)
Valve seat angle 45.00 degrees
Valve spring free length (intake) 50.2 mm (1.9763 inch)
Valve spring free length (exhaust) 50.2 mm (1.9763 inch)
Valve spring out-of-square limit (intake) 2.5 degrees
Valve spring out-of-square limit (exhaust) 2.5 degrees
Valve spring compression pressure (intake) 633.3 - 701.3 N @ 28.02 mm (1.1031 inch)
Valve spring compression pressure (exhaust) 633.3 - 701.3 N @ 28.02 mm (1.1031 inch)
Valve spring installed height (intake) 40.6 - 43.6 mm
Valve spring installed height (exhaust) 40.6 - 43.6 mm
Valve spring installed pressure (intake) 272.1 - 306.1 N @ 40.0 mm (1.5748 inch)
Valve spring installed pressure (exhaust) 272.1 - 306.1 N @ 40.0 mm (1.5748 inch)
Valve spring installed pressure service limit (intake) 274.6 N @ 40.01 mm (1.5752 inch)
Valve spring installed pressure service limit (exhaust) 274.6 N @ 40.01 mm (1.5752 inch)

LH cylinder head Wiring bracket nut and bolt 25 Nm (18 ft. lbs.)
For specifications regarding Intake Manifold bolts, refer to service procedure. Service and Repair
For specifications regarding Exhaust Manifold bolts, refer to service procedure. Service and Repair
For specifications regarding Cylinder Head bolts, refer to service procedure. Service and Repair
For specifications regarding Camshaft Bearing Cap bolts, refer to service procedure. Service and Repair