911 Twin Plug Distributor Conversion

Twinplugging the motor is a performance option, which significantly improves combustion efficiency. The dual spark ignites uniform combustion with the chamber significantly increasing power and smoothness throughout the power band and at the same time improving gas mileage. While this conversion will improve the performance of any motor, it is strongly recommended for engines with displacement increases to maximize the combustion potential of the larger pistons. The twinplug ignition has been used in race application since the mid 1950's and became a standard factory performance feature for normally aspirated 911's in 1989/90 with the Carrera 2/4 models.

The twin plug conversion requires the use of a breakerless ignition distributor. As shown below for 911 SC and Turbo applications, through 1989, the existing distributor is converted to use a Bosch 12 plug distributor cap and rotor. For 911 Carrera's from 1984 to 1989 a signal splitter is used with the C2 tandem distributor.

911 Turbo 1976 - 1989 / 911 SC 1978 - 1983

For carburetor, mechanical or CIS injection engines, this conversion retains the correct advance curve and vacuum retard for proper and legal engine functions. Uses a Bosch distributor cap and rotor. Components necessary:
AND 602 033 EX Distributor conversion, exchange
AND 602 702 00 2nd CD unit - Permatune
901 602 502 00 2nd ignition coil - Bosch
AND 602 907 01 Wiring harness for 2nd CD unit and Coil
AND 602 031 32 Complete 2nd plug wire set
AND 107 347 04 Special camline
930 106 326 01 Sheetmetal - not needed for Turbo engines


911 Carrera 1984 - 1989

For engines with Motronic ignition, this conversion necessary:

AND 903 950 02 Signal splitter with hybrids
930 602 015 01 C2 Tandem distributor
944 602 115 00 2nd ignition coil - Bosch
AND 602 031 33 Complete 2nd plug wire set


Go Back