I have just about completed the wiring for my $2011 GRM Challenge car.

I am converting a 1975 914 to WRX powertrain. The car came as a roller and the 14 pin connector shell was missing. Just dangling wires so I have no reference for pin position.

I just have to connect the battery and have a few wiring connections.

I am only using the following connectoins:

yellow starter wire (pin1 on my 911)
blk/pur tach wire
blue alternator field wire
black alternator wire

The two red wires is my confusion. I think these both go to batt+ Are either switched 12V? On my 911 there is both 12V hot and 12V switched. I would assume the larger diameter wires is 12V hot and the smaller diameter is 12V switched.

Can anyone confirm? Thanks.

I am hoping to fire the engine for the first time this weekend.

The reds go to the battery. One ends up at the fuse panel and the other goes to the ignition switch to give it power.

Thanks Mike,

I just found a wiring diagram on PP.

Here are the assignments.

T14-pin 12 is power to the relay panel direct from the battery
T14-pin 14 is also power to the relay panel through the engine compartment fuse.

Both Pin 14 and Pin 12 attach directly to the battery.

A separate 12V hot connects the battery to the starter and then to the alternator.


There is a separate battery connection that is two red wires coming off a ring terminal at the battery. These go to the wiper switch and ignition switch. A black wire comes from the ignition switch to T14-Pin8 for 12V switched.

I now have everything I need for final engine connections.

With luck I might get the car started this weekend.