1975 Datsun 280z FSM - Spooled up Racing

Engine Mechanical
Unit: mm (in)
L28
Intake
9 (0.354) R-
45.597 to 45.613 _.
(1.7952 to 1.7958) dia. 7.
I
T
6.8 (0.268)
L
i.
Fig. EM-44 Reaming valve guide
1.0 to 1.5 —'
(0.039 to 0.059) R
--39 (1.5354) dia..
1.25
(0.0492)
--32.6 (1.283) dia.-
4. Ream bore with valve guide
pressed in, using Valve Guide Reamer
SetST1103S000.
Reaming bore:
8.000 to 8.018 mm
(0.3150 to 0.3157 in)
5. Correct valve seat surface with
new valve guide as the axis.
Exhaust
EM300
—30 (1.181) dia.--
— 37.580 to 37.596 —
(1.4795 to 1.4802) dia.
Fig. EM-46 Standard valve seat dimensions
Cylinder head recess diameter
VALVE SEAT INSERTS
Check valve seat inserts for any
evidence of pitting at valve contact
surface, and reseat or replace if worn
excessively.
Valve seat insert of 0.5 mm (0.020
in) oversize is available for service in
this engine.
STl1650001
Intake
Exhaust
Interference
fit mm (in)
For standard insert
For service insert
For standard insert
For service insert
Intake
Exhaust
45.000 to 45.016 (1.7717 to 1.7723)
44.500 to 44.516 (1.7520 to 1.7526)
37.000 to 37.016 (1.4567 to 1.4573)
37.500 to 37.516 (1.4764 to 1.4770)
0.081 to 0.113 (0.0032 to 0.0044)
0.064 to 0.096 (0.0025 to 0.0038)
EM436
Fig. EM-45 Correcting valve seat
Replacing valve seat insert
1. Old insert can be removed by
boring it out until it collapses. The
machine depth stop should be set so
that boring cannot continue beyond
EM-10
the bottom face of the insert recess in
cylinder head.
2. Select a suitable valve seat insert
and check its outside diameter.