Fabbing an alt support bracket

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Doppleganger

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Got no response on the other post, so lets try it this way.

I am using a 140A alt. The brackets I am forced to use (due to FI setup) used a smaller 105A alt, so the 140A fits, but not like it should. It fits on one side of the stock mount but one side is a small thin ear. This alt is bigger so wont work with the stock support bracket either. Here are 2 ideas for where I am thinking of making a support bracket for this thing. Would be using .250 steel plating.

Just wondering what your thoughts are if this will work.

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I like What you have drawn. But I see an intake bolt close by too that would be a good anchor point?
Thought about that but to be honest, I'm afraid to mess with it. lol Maybe replace the intake bolt with a stud? Dunno.

The original (smaller alt) went from a boss on the back to a spacer/stud on the exhaust manifold.
 

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I see what you mean about the intake. Maybe a combination of the 2 tying together. Using a stud on the intake would mainly be for lateral support.
 

squaredeal91

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Could make a support bracket from exhaust and that unused hole on power steering bracket and go up to that alternator boss but it might not look clean.
 

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Here's a couple more mock-ups (using the original brace for the smaller alt). One is using the 140's rear boss. Actually like the intake idea - if it can be done correctly.

Biggest thing about that intake is the bolts were torqued in a certain sequence and at a gradual rate - dont want to screw that up in any way.....and this project would do it if it could.

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So, going to the stat housing instead of the intake is off the table?
In reference to the last photo

Or that hole facing forward, under the stat. Is that threaded?
 

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So, going to the stat housing instead of the intake is off the table?
In reference to the last photo

Or that hole facing forward, under the stat. Is that threaded?
This intake has more unmarked threaded holes than I can count. Few of them are listed in the manual but not all. Have found some sites that show them being plugged - others never mention them. Might have to ask Edelbrock if they know what they're for (and with their customer service, I'm not sure I'd believe them anyways). Just figured I'd plug them in the end to be sure.
 

85 Squarebody76

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Got no response on the other post, so lets try it this way.

I am using a 140A alt. The brackets I am forced to use (due to FI setup) used a smaller 105A alt, so the 140A fits, but not like it should. It fits on one side of the stock mount but one side is a small thin ear. This alt is bigger so wont work with the stock support bracket either. Here are 2 ideas for where I am thinking of making a support bracket for this thing. Would be using .250 steel plating.

Just wondering what your thoughts are if this will work.

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I would thread the back of the mounting boss of the alternator (top pic ) and make a bracket from there to the 12 point bolt in the intake manifold.. clean and sturdy too
 

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Just throwing out ideas…

Clock the back half of the alternator clockwise by one bolt hole.

Then the boss behind the valve cover (A) would be in position to use the threaded hole in the bracket (B) or the header bolt (C). Or maybe both the threaded hole and header bolt.

The charge lug and the exciter wire harness should still be accessible

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CalSgt

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Just throwing out ideas…

Clock the back half of the alternator clockwise by one bolt hole.

Then the boss behind the valve cover (A) would be in position to use the threaded hole in the bracket (B) or the header bolt (C). Or maybe both the threaded hole and header bolt.

The charge lug and the exciter wire harness should still be accessible

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Also…. Clocking the housing may make using the other boss more accessible for your other idea
 

CalSgt

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Also…. Clocking the housing may make using the other boss more accessible for your other idea
Also-also…. If you clock the housing, the black center section is attached to the back half so it turns with it.
 

CalSgt

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What is the hole below the thermostat?

It’s possible a flat plate could be cut to shape and connect that hole to the boss. The same plate could be tied into the main mounting bolt with a spacer.

It could be made a little more rigid by welding a tab to tie into the manifold bolts

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Here’s the GMT400 suburban 140 amp support plate for the Vortec setup, maybe it’ll give you another good idea.
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