Specifications - GMC 1990 Light Truck Repair Manual

All Specifications are in INCHES unless otherwise noted.
GENERAL DATA:
Type
Displacement
RPO
Bore
Stroke
Compression Ratio
Firing Order
Oil Pressure (Minimum)
CYLINDER BORE:
Diameter
Production
Out Of
Round Service
Production
T , aper
Service
PISTON:
Production
Clearance
Service Limit
PISTON RING:
C
0
Production
Groo ve
M
p
Cleara nee
R
Service Limit
E
S
Production
S
1 Gap
0
Service Limit
N
Production
Groove
0
Clearance Service Limit
1
Production
Gap
L
Service Limit
PISTON PIN:
Diameter
Production
Clearance
Service Limit
In Piston
Fit In Rod

SPECIFICATIONS

ENGINE SPECIFICATIONS
6
psi @
Thrust Side
Relief Side
Top
2
nd
Top
2
nd
4.3 LITER V-6 6A3-27
6
V
4.3L (262 Cu. In.)
LB4
4.00
3.48
9.3:1
6
1 - - 5 - 4 - 3 - 2
1000
RPM; 18 psi @2000RPM;24 psi @4000RPM
3.9995-4.0025
0.001 (Maximum)
0.002 (Maximum)
0.0005 (Maximum)
0.001 (Maximum)
0.001 (Maximum)
0.0007-0.0017
0.0027 (Maximum)
0.0012-0.0032
Hi Limit Production + 0.001
0 010 0.020
. -
0.010-0.025
Hi Limit Production + 0.010
0.002-0.007
Hi Limit Production + 0.001
0.015-0.055
Hi Production +0.010
0.9270-0.09273
0.0002-0.0007
0.001 (Maximum)
0.0008-0.0016 Interference
F-6344