matviar

I am cloning a 1970 Cutlass to 442 specs. The original alternator is externally regulated with a voltage regulator mounted to the firewall. The manual says 1970 442's used an internally regulated alternator. I want to go with the internally regulated one. My question is, do I need the firewall mounted regulator, or do I need a different one? Is my cutlass wiring harnesses compatible or need modified? Any info would be very helpful.

joe_padavano

The whole point of the internally regulated alternator is that the regulator is internal to the alternator, not on the firewall. The harness needs to be modified to bypass the old regulator for this to work.




FYI, real 1970 442s used a unique alternator with an open face and a distinctive rear housing. Correct ones are hard to find and priced accordingly when you do.

matviar

Thanks Joe. I have an alternator (new or rebuilt) where as the back of it looks like the one pictured, but the front is not openfaced. So You are saying, omit the cutlass firewall regulator and make the harness mods?

joe_padavano

If you really have an alternator that looks EXACTLY like the one in the photo above, sell it to a restorer and pocket the several hundred bucks. I'm guessing the one you have looks more like this, without the raised diamond shaped cooling fins:



One more time:

matviar

Yes Joe, the alt I have looks very close to the one You just pictured, except mine has 5 round holes on the back where Yours shows 8 slots. Also, I had to remove a rubber square to expose the field wire tabs on the top.