Does anyone have a picture of the bracket that fits between the alternator and the cylinder head ? Basically it is a spacer with a tab to bolt to the alternator. It also has to be sized for a 3/8 bolt for the big block head.

what year?

I can take a picture of mine but mine is just a piece of 1/2" chrome pipe nipple slid over a stud that is 3/8" on the alternator end and 7/16" on the head end.
It doesn't bolt to the back of the alternator.

I have several old style alternators that have a 7/16 hole for the long bolt.

The thread in the big block head is 3/8.

I am working on a 66 car but am using the long water pump with newer style passenger side alternator setup. The top bracket and the bracket from the water pump are installed, so just need the spacer piece that the alternator swivels on.

The hole in the alternator has to be 3/8 and also the spacer piece that originally would have bolted to the back of the alternator.

How long is the spacer between the alt. and cylinder head supposed to be? I have a 70 396 and my spacer has a tab welded to it. I dont think its the right size because my alt. belt is off-centered. I think my spacer might be for a small block. Thanks!

I have several old style alternators that have a 7/16 hole for the long bolt.

The thread in the big block head is 3/8.

I am working on a 66 car but am using the long water pump with newer style passenger side alternator setup. The top bracket and the bracket from the water pump are installed, so just need the spacer piece that the alternator swivels on.

The hole in the alternator has to be 3/8 and also the spacer piece that originally would have bolted to the back of the alternator.

I have seen people drill out the hole through the alternator to 7/16" and use a 7/16" bolt but don't think I ever saw a 3/8" threaded hole in the head.

Not sure how long the spacer is supposed to be but I did find a couple of pictures with no deminsions.

Not totally for sure but I think the distance from the head to the alternator should be 3 5/16" so the spacer would be that long less the thickness of the nut on the stud and the "tie bar".
(like I said, I can't really see any purpose for that bar)

My home brewed spacer is shorter (long story)

When I got my engine it was a basket case and the first time I put it together, I used a 3/8" bolt with a helicoil in the head because I didn't know any better.

When that broke on the way to Nashville, James Hinshaw gave me the proper stud which I put in and ground the spacer shorter because of the nut on the new stud.

Then later that new stud broke off and I borrowed a drilled out alternator and 7/16" bolt from my friend's car (in a trailer) to get home.

After I got home that time I drilled out my alternator, put 3 flat washers behind the spacer to make up the amount I had ground off and put a 7/16" bolt in.

It has held OK that way for a few years now
(keeping my fingers crossed on the way to Nashville next time) :)

I just measured my alternator spacer, and it is 3 1/4 inches. This makes the alternator 3 1/2 inches from the cylinder head when mounted ( 1/4 inch added for the thickness of the nut). Is this the correct distance for a 70 396? Again, I have the spacer that has a brace welded to it, the spacer and brace are not seperate pieces. I dont think I have the right setup. Thanks for any help!

The picture shows the correct bolt to screw into the head and then the spacer and alternator slip on the thinner end and is held in place with the nut and washer. This part is available on ebay and through greenwoodchevy.com. Just search ebay for alternator and mount and it will be there for BB chevy.

There are two other options:

1. drill and tap the head for a helicoil that will accept the long bolt that fits through the alternator (I do not want to drill the head)

2. ream the hole in the alternator and spacer to the same size as the hole in the cylinder head and use one long large bolt. This seems like the best option other than the original.

thanks for the replies

I will probably go with option 2 cause I don't have time to wait for greenwood to ship.

Well finally got the alternator installed perfectly lined up.

I decided to drill out the swivel point hole in the alternator from 3/8 to 7/16. Also drilled the spacer that bolts to the alternator. Then used a 6 inch long 7/16 bolt and bolted it up.

It was a very easy process and hard to go wrong because reaming the 3/8 hole in the aluminum alternator with a drill bit is just so easy.

The 7/16 bolt is also going to be stronger than the original setup that uses the stud with 7/16 shank going into head and the 3/8 shank for the spacer and alternator.

And it almost looks stock.

:thumbsup: Cool, I agree, I think the 7/16" bolt is going to hold better than the original stud.