Cdi box location

[23 Ranger]

1985 Porsche 911 coupe. Trying to find the CDI BOX. I can’t find it in engine compartment. Removed fuse box and mounting plate. Coil is mounted next to plate. Any ideas where they hid it ?

[john walker's workshop]

It doesn't have one.

[ischmitz]

Check under the driver's seat. That's where the "brain" of the engine resides. It takes care of the electronic fuel injection and the ignition.

A 3.2 engine uses a Bosch Motronic where the coil is driven directly from the ECU (engine control unit). Some also refer to this box as DME (digital motor electronic).

Then there is a small black relay next to it and that is the DME relay.

[23 Ranger]

Thanks, thought that might be the case but wasn’t sure. Was going to install a MSD 6al box, but now I’m not sure. Any thoughts ?

[ischmitz]

The topology of the 3.2 ignition is a "transistorized ignition" where the traditional points are replaced by an electronic switch inside the DME. The DME controls timing based on engine load and RPM.

The Bosch CDI and MSD6AL and other aftermarket systems a capacitive discharge ignition systems. They are a step below on the evolutionary ladder. The development went from points to CDI to transistorized ignition systems. Unless you wanted to remove the DME altogether and revert back to a carburetor and distributor-controlled ignition advance there is no practical way to even integrate a CDI ignition to a DME car. So the simple answer is: NO NEED

[23 Ranger]

Thank you !