Porsche 911 TURBO - 1989 Workshop Manual page 161

CHECKING IGNITION TIMING CONTROL
Requirements: Ignition timing is set correctly. Check timing angle as follows.
Europe Version
USA Version
..0 + 0 .
Igmtlon angle must be 0 -3 at Idle speed of
+
950 -50 rpm (vacuum hose connected)
0+ 0
Ignition angle must be 26 -3 BTDC at engine
speed of 4000 rpm (vacuum hose disconnected)
If specifications are not met, remove distributor and check on test bench.
CENTRIFUGAL ADVANCE CURVE TURBO ENGINE
BTDC
2~
=:~:tt
&
15°,
f-
y
z
1__-
I ~,o
I I .~
-I
I , ,~ ~ ~ .I
0 1000
Distributor Shaft Speed (rpm)
2000 3000
4000
Printed in Germany -I. 1976 Checking Ignition Timing Control
28 -3