Cylinder Head Bolts - Revised Torque Specifications
File In Section: 6 - EngineBulletin No.: 87-61-27
Date: August, 1998
SERVICE MANUAL UPDATE
Subject:
Section 6 - Engine Mechanical Revised Torque Specifications for Cylinder Head Bolts
Models:
1997-98 Chevrolet Corvette
1998 Chevrolet Camaro
1998 Pontiac Firebird
with 5.7L V8 Engine (VIN G - RPO LS1)
This bulletin revises the torque specifications for the fastener tightening table and cylinder head installation procedures in Section 6 of the Service Manual, due to a bolt material change.
Procedure
1. Cylinder head bolts (first pass all M11 bolts (1-10) in sequence) 30 N.m (22 lb ft).
2. Cylinder head bolts (second pass all M11 bolts (1-10) in sequence) 90 degrees.
3. Cylinder head bolts (final pass all M11 bolts (1-8) in sequence - excluding the medium length bolts (9 and 10) at the front and rear of each cylinder head) 90 degrees.
4. Cylinder head bolts (final pass M11 medium length bolts (9 and 10) at the front and rear of each cylinder head in sequence) 50 degrees.
5. Cylinder head bolts (M8 inner bolts (11-15) in sequence) 30 N.m (22 lb ft).