I made a small block low mount alternator bracket

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rmchrgr

Skate And Destroy
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I've been thinking about doing this for years. As far as I know, no one currently or has ever made a low mount alternator bracket for a small block Mopar. There are a few for big blocks but not a one for the lowly small block. I'm not sure why that is since they are available for just about any other American V8 you can think of. What that means is that if you want one, you're going to have to make it.

The top bracket is based off a Denso 60a alternator from an '80s Toyota and not a factory alternator but it could probably be made to work either way. Densos are great alternators but there are two particular caveats to them - when mounted in the "normal" position, the wiring harness ends up very close to the #2 header. While it may not be that big of a deal it's obviously preferable not to have any wires in close proximity to heat. The wires on stock units are located more towards the water pump and on top of the alternator. Additionally, the belt ends up being fairly long and is not supported by anything within it's span. Again, probably not a huge deal but why not try to see if there is a more elegant solution.

So after years of hemming and hawing about it, I decided to knock one out so I could have it done for when my engine goes in the car. It took a bit of thinking on how to accomplish this. The method that was easiest (for me) to execute involved welding two old accessory brackets together and cutting them into the shape I wanted.

First, I started with a scrap piece of thin plate and drilled the holes based of lots of redundant measuring. The intent was to use what became the template as the actual bracket but once the shape was cut out, I laid it on top of the old brackets and realized it would be better to weld the old brackets together. Turns out a big block alternator bracket happens to have the exact spacing needed between the bottom hole on the water pump side and the lower hole on the cylinder head so there was only a need to locate and drill one hole. Plus, the OE brackets were the correct thickness - the thin plate might have worked but it would have needed washers welded on behind the holes to make it the same depth for proper pulley alignment. Too much work. So ultimately the plate became a template to drill and cut the welded-together brackets into the desired shape. Didn't take much to finish it after that.

This is the thin plate that was intended to be used as the actual bracket before it was cut out.
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Roughed out template.
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Might have been acceptable strength-wise just not thick enough for pulley alignment.
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I didn't take pictures after welding the two old brackets together but this is what ended up being cut off after they became one. The BB alternator bracket is on the left. I'm not sure what the triangular one on the right was for. Fully welded both sides.
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Template.
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Needs some finish work and paint but this is basically what the final product will be. The hole to the left of the adjustment bracket bolt is for the heater hose holder-upper thingy on a BB. The adjuster arm is from the AR Engineering Denso 60A bracket set.
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Top view. Note the divot in the top edge - that's the bottom of the cut-out in the BB alternator bracket. Not sure If I'm gong to leave it like that or not. You can kinda make out the wiring harness pigtail under the spacer. Much better there than 1 1/2" from the header. The wires will run up the front and towards the firewall along the valve cover rail like normal.
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Works! I'm stoked on how this came out. My preference would have been to make it one piece but I don't have enough of the proper thickness material to make another one. Hope you's dig it.

- Greg
 

Nice! When you look for a belt, this helped me. Might help you.
Measuring with a flexible tape measure, I come up with a hair under 30" with at least 1" travel either way on the adjuster slot. Dayco lists #5060295 a 29.53" 6-rib belt which fits '17-'22 BMW M760i plus some older Infiniti and VW models.

The part number is good though as my local NAPA lists generic ones for around $32. Little pricey for a belt but it will last forever.

The one I was using previously with the alternator in the OE position was 39.33" long. I'd say a 10" shorter belt is a "gain".
 
Nice work Greg. Love seeing stuff like this.
Thanks Rob!

Nice looking part! You oughta trace it on a piece of paper and make copies. You'd probably be able to sell them for a few bucks.
I thought about that but that's as far as it went. I guess if someone really wants one I could do it.

Those particular Denso 60a alternators are tough to find now which makes the market for this part even smaller. As far as I know even @AndyF never saw the need for a small block one though he does make one for a big block.

It really wasn't that hard to make, just tedious. If a hack like me can do it anyone can. The measuring was the most difficult aspect of it. I'm actually impressed with myself that it lined up as well as it does without having to fudge anything. And for once my welds were good too.

It was a real stroke of luck to have that BB alt. pulley on hand, it just worked out perfectly. Not saying that's the only way to accomplish this but it saved me a lot of work. Once I figured how to incorporate that part the rest went very quickly.
 
You fixed something that was annoying you regarding how things were aligned. I did the same thing on a LA roller block, just a little more extreme. :)


Out of the way and down low

AltBracket06.jpg
AltBracket03.jpg
 
The gain from this is a functioning part.

Same could be said for the stock mounts.

I appreciate the explanation about moving it away from the heat. I was more engaged in how the mounts were made, and not as much as I should've been in reading the text. I do like the idea of a lower coG.
 
Same could be said for the stock mounts.

I appreciate the explanation about moving it away from the heat. I was more engaged in how the mounts were made, and not as much as I should've been in reading the text. I do like the idea of a lower coG.
I have a few friends that detest modified stuff on cars and they invariably roll their eyes when I tell him about some modification they believe I didn't need to do. I just laugh, they'll never get it. Often when you modify stuff you have to figure out ways to get around "problems" you create which wouldn't exist otherwise. Stock is boring.

That said, there's nothing wrong with the factory execution of the front accessory system if everything else is configured as such. Mine's obviously not so once you cross that line everything is fair game.

And again, the other main reason for this was belt length. I've pitched belts going down the track. Coming back up the return road seeing my temp gauge at 225 and missing the next round was no fun so the shorter belt was a priority.
 
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