Denso alternator upgrade - not the 60amp mini

fury fan

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Anyone retrofitted a V8 pre-Magnum-style Denso alternator to their bigblock? Not the 60amp Toyota mini-alternator that Mancini, AR Engineering, etc, sell as a kit, but the alternator used on late 80s Diplomat, truck, van with V-belts.


Reasons:
  • for the cost involved, I want more than 60 amps total of the Toyota 'mini' kit.
  • Some of the vendors of the kit mention it has a 'correct' pulley
  • I want a parts-store alt with a warranty - not a more-expensive mail-order one.
  • I could buy just the conversion brackets, but I don't know if the parts-store Toyota pulley is spaced correctly, the Rock Auto pulley is different than what is shown in the mini-kit pictures.
  • from what I see of the Toyota alt, it maybe was only used for a few years in the mid-80s (as a V-belt anyway)
  • The Mopar Denso is avail with a V-belt in the late 80s and then with serp all thru the Magnum years, so it'll be available for a long time still
  • I believe the pulley spacing of the Mopar alternator will work as a straight-shot to my water housing (still needs verified, though).
  • And the Mopar alt is available in 90 amps (or 120 with a larger case)

I've done some mockup evaluation and it just doesn't fall into place. The battery stud on the rear is in a bad spot, it buries it in the back against the block. It has a shield around it, so not an elec short issue (unless in a hard collision) but I'm not sold on that yet. Also - it's so close to the block that the alt can only rotate a little bit until that shield hits other bosses on the block.

Using other mounting bosses on the block (for the long pivot bolt) simply moves this connection to other bad spots. There's one boss that looks promising, it mounts the alt a little high like a 65-older AC setup, but that boss is on the 516 heads (my mockup) and I want to install on 906 and 452 -- and there's a freeze plug there on those heads.

It does not look like the elec connections on the alt should be clocked, as then the 2-ear pinching on the long pivot bolt would be lost, and would require a complex bracket to tie the halves together (there are only 4 small screws holding the case together). I feel like mounting the alt via the front case and having the rear float on those 4 screws is asking for durability issues down the road.

Any thoughts/ideas/experience?

Denso mini-kit.JPG


Mopar Denso V-belt type.JPG


Mopar Denso V-belt type - installed 2.JPG
 
I am no help but watching to see. I wanted to put one of these on my Barracuda to save weight and clear the elephant ears better.
 
I have one in a Challenger with 383. I'm running it with stock voltage regulator. I had to make some spacers to get the belt line correct as well as work with the plastic battery connection cover. I filed the locating tab from the cover and rotated it so that the cable exits in better direction. The clearance to the head is quite narrow but still enough.

Best update I have made! I also made sure that I got real denso and not some knock off. Mine was a rebuild unit from ebay for something like 100usd if I recall right
 
I have one in a Challenger with 383. I'm running it with stock voltage regulator. I had to make some spacers to get the belt line correct as well as work with the plastic battery connection cover. I filed the locating tab from the cover and rotated it so that the cable exits in better direction. The clearance to the head is quite narrow but still enough.

Best update I have made! I also made sure that I got real denso and not some knock off. Mine was a rebuild unit from ebay for something like 100usd if I recall right

Can you post some pictures, thanks in advance.
 
Can you post some pictures, thanks in advance.
Hey, I was gonna ask him that...:(

That thread was a big help, esp the installation picture at the end, I saw it previously but didn't look past the 100amp stuff.

I had heard that this Denso alternator was a drop-in for the factory brackets, but I'm not sure why my mockup isn't falling together so well - maybe I'm just being too picky about the charge wire location. The Honda alt mentioned at the end of that thread is interesting also.
 
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I was under the impression that this Denso is a plug n play swap. No?
I'm not sure. There's this picture from the other thread that suggests it is, but I'm not 100% sold on the charge wire location. Not saying it's wrong, just that I wish it was different, and I'm trying to find something a little better.

Beat ya by 2 min:lol:
No, by less than that, I was typing when I saw something show up that said 'new responses added'. It took 2 min because I had to undo what I had just typed...

dscn9405-jpg.74700
 
Already over midnight in Finland so no pics for tonight. I will try to get some pics tomorrow. It just means some car tetris in the carage as Challenger is currently on the lift up in the air and my Fury us parked below it :D
 
Don't inconvenience yourself that much, if yours looks like the orange engine pic I just re-posted above then that's enough info for me to run with.
 
I have been running this alternator for a while now - works fine. Battery wire location is not an issue. It comes out on the side and does not interfere with the block or anything else. You can use Honda alt. that is even smaller in size and will give you even more clearance.
DSCN6660.JPG
 
I have been running this alternator for a while now - works fine. Battery wire location is not an issue. It comes out on the side and does not interfere with the block or anything else. You can use Honda alt. that is even smaller in size and will give you even more clearance.
View attachment 82424
Plug n play?
WHICH Honda alternator...
 
Existing brackets should work. You might have to use washers to line up the pulley (it depends of what pulley you will get - it has a bolt on style, not a press fit, but there are so many of them for $10-$15). If you don`t want to spend money - go to a local junk yard, get one for $20 and check the fitment. I got mine for $20 off Ebay. When I received it I noticed it had fan blades bent. I let the seller know and received a full refund, so I got mine for free ))
 
I've seen some folks comment on bolt-on pulleys, to get them at Summit, parts store, etc, but nobody shares any info on shaft dia, belt offset, etc to know what pulleys to look for. My suspicion is that they are not SAE standardized?
 
I measured the alt. shaft diameter and ordered a proper pulley from Summit (they list all dimensions). In regards to belt offset - mine lined up perfectly, but that can be fixed with washers on the brackets.
 
Pulleys, brackets, shimming, wiring, Oyeeee.
I'll spend the money on an alternator specific to my application. There's enough of them out there.
 
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