Porsche 928 Workshop Manual page 497

928 Ignition System
28
6. Attach vacuum hoses. Ignition timing must
be 0 t 4' when engine runs at idle speed
800 i 50 rpm).
Remove distributor and check it in a distributor
test bench. if specifications in points 5 and 6
cannot be held.
Note
1. Ignition must be off when connecting tester to
ignition coil.
2. The dwell angle is not adjustable and does
not need to be checked.
l
Printed in Germany
Adjusting Ignition Timing
28 - 5