Ignition Timing

With engine at normal operating temperature, disconnect hose to distributor. Stop engine and connect timing light to No. 1 cylinder wire and tachometer to ignition coil.
Start engine and increase speed to 3000 RPM. Timing should be 31°BTDC. Adjust timing as necessary by turning distributor. Increase engine speed to 5500 RPM and check that timing is now 33-37°BTDC.
Return engine to idle and reconnect vacuum hose to distributor. Timing should now read TDC. If not, distributor should be removed and bench tested.

IGNITION TIMING SPECIFICATIONS

Application

RPM

Timing ⁽¹⁾

All Models

3000

31°BTDC

⁽¹⁾	With distributor vacuum hose disconnected and plugged.

Fig 1: Ignition Timing Marks

Courtesy of PORSCHE CARS NORTH AMERICA, INC.