Install Fridays: Delco CS144 type Alternator into a 1982 Porsche 924 Turbo

Installed the alternator with no trouble. Only had to make 2 changes: 1) The bolt holes in the CS-144 are larger (3/8") than the bolts and bolt holes in the original Bosch alternator (8mm (approx.5/16")), I cut and formed 2 sleeves from a piece of copper water pipe to make the 8mm bolts fit snugly in the 3/8" holes. 2) I could have used a larger v-belt, but; didn't have one on hand, so; I lengthened the slot in the adjustable mounting bar (to the left of the alternator in the photos) by about 1.5 or 2 inches. The bar had very little room for adjustment to begin with - only about 2 inches. I drew a line across the bar at the original mounting point for the Bosch alternator so you can see the difference between the Bosch and CS-144 mounting points when using the original Porsche spec v-belt. That can be better seen in the second photo.

For wiring, I made 3 connections: 1) the red battery wire 2) a ground wire from the engine to the alternator housing (used the 3/8" threaded hole at the upper-rear of the alternator nearest to the engine block) (The Bosch alternator had a ground wire here since all the mounts are cushioned with rubber.) The old wire can be reused if the original v-belt is used. If a longer v-belt is used, that will probably move the ground wire attachment points too far apart, but; it's a good idea to replace the old ground wire anyway. They're made of bare braided copper and most have probably gained some resistance over 20 years of exposure. 3) The car has a battery light that lights with the ignition on and the engine not
running. I took a voltage reading from the final small gauge wire attached to the Bosch alternator. It read approx. 1.4 volts. I connected this to the "L" wire on the CS-144 with a single wire plug (can be seen running alongside the red wire to the right of the alternator in both photos). That's all.

The Bosch was a 75 amp alternator. Voltage readings taken from the cigarette lighter port gave approx 12.9V with the engine running at idle and no lights, interior fans, audio, wipers, horn, nothing turned on. With the radio turned on, the voltage would drop by .65V to approx 12.25V. Then with lights and windshield wipers and ventilation fan running, that took it down below 12V. Not good...
With the CS-144, I get approx 14V with the engine idling and nothing electrical turned on. It still drops by .65V when I turn the radio on (to 13.35V). Then with all the usual nighttime electrics on - radio, headlights, ventilation fan it shows approx 12.8V. One time I saw a reading of approx 12.3V. That was on my first time driving it after the CS-144 was installed. I had driven about 10 miles and it had been idling for a few minutes when I looked at the meter and saw 12.3V. The lowest reading I've seen since then is approx 12.8V.