split63

Prior to '72 GM mounted the Alternator on the Left Exhaust Manifold.
In '72, GM introduced bracket 3951337 which changed the mounting to the front of the head (picture below)

Question, does this change the position of Alternator relative to the water pump/crank pulley? Trying to understand if it would work on a '70 LT-1 with headers
Is a different belt needed; the Alternator seems positioned much higher.
I guess there is no hood interference, otherwise how could they have used it on a '72
I notice that it has a different upper brace....can the '70 brace be used instead?

72 Alternator bracket



Stock '70 Alternator position



'70 Alternator position

carriljc

I used one of those on my 68 to replace the lousy header bracket since my head had holes in the head. Lined up just fine.

[QUOTE=split63;1604127290]Prior to '72 GM mounted the Alternator on the Left Exhaust Manifold.
In '72, GM introduced bracket 3951337 which changed the mounting to the front of the head (picture below)

Question, does this change the position of Alternator relative to the water pump/crank pulley? Trying to understand if it would work on a '70 LT-1 with headers
Is a different belt needed; the Alternator seems positioned much higher.
I guess there is no hood interference, otherwise how could they have used it on a '72
I notice that it has a different upper brace....can the '70 brace be used instead?

Sigforty

For headers just get the Hooker brackets. They bolt together and go around the cylinder 1 header tube.
Header bracket
https://www.holley.com/products/exha...parts/10927HKR
Alternator bracket
https://www.holley.com/products/exha...parts/10928HKR

split63

That's what's on there now. Looking for something a bit more sturdy that is not sitting on the exhaust and potentially conducting heat into the Alternator

PJO

I would think this would work without issue. The change was due to the same exhaust manifold was use on both sides of a 1972 small block. GM reduction in cost plan. I would use both of the brackets as they were designed for use with this change in design.

carriljc

I've had them both. Alternator Bracket 3951337 is a LOT better than those header bracket contraptions. I recommend it. You can probably find one cheap on flea-bay.... or from early 70s Chevy pickup trucks. Cast iron and sturdy.
Don't buy the first one you see....there's a ton out there and some of these scam artists are charging outrageous prices for them. Just looked and there is one for 27 bucks on fleabay (and others for ridiculous prices in the $150+ range). It's cast iron so it'll last forever.

C3 Stroker

This setup works just fine.......it positions the alternator away so the headers don't even come into play.

Barry's70LT1

I'm been using that same mount bracket for 50 years, with headers. In 1971 that bracket was used on a truck.
The best I remember, I used the same '70 upper brace, as my upper brace doesn't look like that one. My brace is the same width/thickness for the entire length.