1 Wire 3G Alternator

So we are having trouble with the Mustang running rough. It's cold outside, but there seems to be more to it than that. After a bit of engine tuning, we found that the car was running fine until we turned on the headlights. Then the engine would bog down, rev up, bog down, rev up. Turn the lights back off and the car returns to running well. So, this would be at least the 3rd issue we have had with the alternator, battery and external voltage regulator. We have replaced wiring harness connectors, the regulator, the alternator, and the battery over the past 2 years. We now have a bit of experience under our belts, and I did some research on a 1 Wire Third Generation Alternator conversion. Essentially, this is a swap of the original alternator at 55Amps with an alternator from a modern Third Generation Mustang with an internal regulator and outputting 130Amps.

So we ordered the wiring harness required off of ebay, and a new alternator off of Amazon.

One tricky part of this upgrade, was that we would have to replace the serpentine pulley from the modern alternator with the original v-belt pulley from the classic Mustang. We would love to upgrade to a modern serpentine pulley system as well, but that would require replacing the water pump pulley, and the crankshaft/balancer pulley. We have not been able to find suitable replacements so far, and the upgrade kits for this are in the $300 and up price range. We'll just keep it classic for that price.

Once we got that in place, it was time to install the new alternator.

 Here we are, all installed with the v-belt pulley.

Once that was done, we wired up the alternator. 1 Wire in this case, really means 2 wires. 1 wire to the ignition to turn on the alternator coils, and 1 wire to connect the output to the battery. We used some jumper cable wire, and a few good solid connectors and wired this up to the battery, and then on to the starter solenoid for a nice clean and heavy gauge connection.

I can't even count the number of wires that were involved in the old system. 3 at the alternator, a handful at the external regulator, and the output was run through the dash to give a Charge/Discharge gauge readout. We'll replace the Charge/Discharge with something else later, perhaps a 10-16V gauge. At rest, the system is roughly 12V, when the alternator is on, it's somewhere around 13V. If the engine is running and the alternator is not functional, the voltage is somewhere around 11V.

LED Turn Signals

Upgrading the turn signals to LEDs is a fairly simple process, with the exception of adding in the LED compatible relay. We ordered up a set of LED turn signals to clean up the look of the front end a bit, and to help with visibility.

The LED turn signal comes as a plug in module, you replace the existing light bulb, and lens with the LED assembly.

Plug in module

 The turn signal relay is located in the car, under the driver's side dash. Here we are with the LED flasher installed, and a test lead connected to the new ground wire required by the flasher.

 Once we proved that this was working as expected, we permanently attached the ground lead to a screw on the frame of the dashboard.