Alternator Upgrade
How many times have you been on the way home from a cruise in the evening
and the headlights seem a bit dim, or going through town at an intersection with
the turn signal on, it blinks once in a while?
The problem comes from the 60’s and early 70’s alternators.
They are an Externally Regulated Alternator (ERA), which means that
voltage output is controlled manually by means of a regulator.
In its day, that was great. But
over the years this has improved.
In the mid 70’s Chevrolet came out with an Internally Regulated Alternator
(IRA). This new version is controlled electronically, which gives a
more steady and constant voltage output. ERA
models did not put out a lot of amperage. The
highest was rated was a 63 AMP alternator. The newer IRA models put out as little as 65 AMP, and a few
manufacturers make some models over 100 AMP’s.
Upgrading to a newer alternator is not a very difficult job.
When buying an alternator I will ask for a 78 Caprice with A/C.
This is about a 78 AMP alternator.
Installing the alternator is no different than the one you pull off the car.
The large wire (normally red) goes to the back of the alternator where
the (+) post is, (the stud with a nut on it). Wiring the new alternator used to
be a little confusing and also required cutting of the factory wiring harness.
However Original Parts Group and Year One both offer
conversion harnesses for this job. Original
Parts Group part # is 27555 and Year One part # is HU30.
This makes it very simple to convert. Plug
in the adapter to the alternator and then to the harness.
Locate the external regulator (normally found on the core support on the
drivers side). Unplug the flat
four-wire connector from the regulator and install the adapter to the connector.
Start up the car and turn everything on. Turn
on the turn signals and watch them blink, notice brighter headlights and tail
lights. This also prolongs battery
life by keeping the charge at a steady rate.
This can also be done without the harness adapters, but requires some
cutting and splicing of the factory harness.
For additional information or tech tips contact
the author!