Contents: General characteristics ↧ Cylinder head ↧ Valves and related components ↧ Crankshaft and connecting rods ↧ Cylinder block ↧ Pistons and piston rings ↧ Camshaft ↧ Tightening torques, Pounds-feet ↧
General characteristics
RPO code - L27
VIN code - L
Cylinder displacement: 231 cubic inches
Cylinder Compression Pressure - Minimum 100 psi
The maximum difference in pressure in different cylinders is 30%
Firing order: 1-6-5-4-3-2
Oil pressure - 15 psi at 1100 rpm
Cylinder head
Maximum allowable deformation is 0.003" in a 6" section/0.006 total
Maximum allowable depth of scratches is 0.010 inches
Valves and related components
Valve chamfer width-1/32 inch
Valve seat chamfer angle - 45°
Clearance between valve stem and guide bushing
- Intake - 0.0015-0.0035 inches
- Exhaust - 0.0015-0.0035 inches
Free spring length — 1.981 inches
Valve spring pressure:
- Closed — 80 pounds with a length of 1.75 inches
- Open — 210 pounds with a length of 1.315 inches
Spring Mounting Height: 1.690"-1.720"
Crankshaft and connecting rods
Crank pin:
- Diameter - 2.2487-2.2499 inches
- Bearing clearance - 0.0008-0.0022 inches
Maximum taper is 0.0003 inches
Connecting rod end play - 0.003-0.015 inches
Main bearing journal:
- Diameter - 2.4988-2.4998 inches
- Bearing clearance - 0.0008-0.0022 inches
Maximum taper/out-of-roundness is 0.003 inches
Crankshaft axial play (at the thrust bearing) — 0.003-0.011 inches
Cylinder block
Cylinder liners:
- Diameter - 3.800 inches
- Maximum cylinder ovality is 0.0004 inches
- Maximum cylinder taper is 0.0005 inches
Pistons and piston rings
Clearance between the piston and the cylinder walls (44 mm from the top edge of the piston) — 0.0004-0.0022 inches
Piston ring gap:
- Compression rings - 0.010-0.025 inches
- Oil scraper ring - 0.015-0.055 inches
Piston ring groove clearance:
- Compression rings — 0.0013-0.0031 inches
- Oil scraper ring - 0.011-0.0081 inches
Camshaft
Bearing journal diameter: 1.785-1.786 inches
Bearing clearance - 0.0005-0.0035 inches
Cam lift:
- Intake valve - 0.250 inch
- Exhaust valve - 0.255 inches
Tightening torques, Pounds-feet
(unless another unit of measurement is specified)
Main Bearing Cap Bolts:
- Stage 1 - 26
- Stage 2 - Turn 50°
Connecting rod bolts:
- Stage 1 - 20
- Stage 2 - Turn 50°
Balance shaft gear bolt:
- Stage 1 - 14
- Stage 2 - Turn 35°
Balance shaft holder bolts - 22
Camshaft Sprocket Bolt:
- Stage 1 - 74
- Stage 2 - Turn 105°
Flywheel to crankshaft mounting bolts:
- Stage 1 - 11
- Stage 2 - Turn 50°
Note: Additional tightening torque values are provided in parts 2.2.
The article was reprinted from the website «CHEVYMAN.ru»