Porsche 911 TURBO - 1989 Workshop Manual page 160

Ignition System
ADJUSTING IGNITION TIMING FROM 1978 MODELS
Adjusting Values:
Europe.
R.o.W.
USA:
0
29 before TDC at 4000 rpm
After adjustment of the ignition timing. check
ignition timing control (see page 28 -4 c).
+ 0 +
10 -2 after TDC at 1000 -50 rpm
+ 0 +
5 -1 after TDC at 1000 -50 rpm
California,
Japan:
Adjustments are made when engine oil has a tem-
perature of approx. 800 C. Pertinent mark on pul-
ley must align with notch in blower housing at
specified engine speed.
Europe version requires the detachment of vacuum
hose at distributor. It remains connected for USA,
California and Japan versions.
Adjusting Ignition Timing
IV. 1981 -
Printed in Germany
28 -2 b