how to install a gm 105 amp alt into your datto

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bonvo
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how to install a gm 105 amp alt into your datto

Postby bonvo » Tue Nov 19, 2013 10:21 pm

alright as you guys might know i now have a 105 amp alt in the car and this is how i did it


things you will need

1: gm 105 amp aternator (comes out of newer astro or truck)
Image
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2: 3 feet of wire any color about 16 gadge

3: solder heatshrink and electrical tape and big "eye" type end

4: gm alt plug as shown
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5: double v belt alt pully
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6: chunk of steel 1/4 inch thick by 1 inch wide by 7 inches long

7: a few nuts bolts and washers of varying sizes

8: dye grinder with a cut off wheel plasma cutter somthing to cut steal acuratly with, a drill with a 1/2 inch chuck and a 1/2 inch drill bit

alright the first thing your gonna do is your going to remove the serpentine belt pully that comes on the alternator your not going to be using it i used a big pair of channel locks and the apropriate sized socket do with this as you please

next install the twin v belt pully again i used channel locks and socket

remove original alternator and place the new one in its place you will notice that the lower mounting is totally wrong we will deal with that

posistion the alternator so that both mounting points are close to the block and run a bolt threw the existing belt tentioner and the upper mount on the alternator
you can see in this picture that the belt lines up with the outer grove on the pully when bolted to the stock tentioner (note it may not line up exactly if its a little off bend the tentioner bracket a little)
Image

next turn your attention to the lower mount you will see that the lower mount on the alternator and the mount on the block look like they will never work (new alternator compared to old one for referance:
Image)

first thing your gonna do is take your 1/4 inch steel peice and cut it in half leaving you with 2 chunks about 3 1/2 inches long drill two 1/2 holes one on each end the holes should be about 3 inches center to center
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grind down the edges so the corners arent shap
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place brakets on the original alt mount and blot them down loosly this creates the type of mount that is needed for the new alternator but it is wider then the mount on the alternator you will need to make spacers we used some tubing we had floating around i would give you measurements but each factory alternator braket is different this is the only part you will have to measure and cut yourself

after you have made the spacers run a long bolt thew the lower mount of the alt and the newly created mounting brakets
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you may need to buy a new belt (i did) so you will have some adjustment but with this set up the farther out on the adjustment you go the farther away the alt gets from cutting the lower rad hose

now we move onto wiring this is a breeze

looking at the stock witing there is the T plug the white wire with the small eye on it and a black wire with a small eye on it tape the T connector and the black wire back out of the way take the white wire and put a bigger eye on it so it goes over the pole on the gm alt

next solder about 3 feet of wire to the wire on the gm plug and plug it into the alternator

run the wire along the stck wiring harness up to the voltage regulator unplug the regulator and cut the white with red stripe off the connector and connect your new wire from the gm plug to it (only reason its a butt connector here is because i ran out of soder
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stuff the rest of the voltage regulator plug out of site

and badda bing badda boom this is the end result
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if you have any questions dont hesitate to ask i can answer them
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noflers
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Re: how to install a gm 105 amp alt into your datto

Postby noflers » Fri Aug 12, 2016 6:24 am

Do you know the part numbers on the alternator and the double-v pulley?
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Taterhead
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'72 510 - Sons
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Re: how to install a gm 105 amp alt into your datto

Postby Taterhead » Fri Aug 12, 2016 8:58 am

He hasn't been here in probably 2 years but this is from another site that he wrote up. Maybe it'll help ya out.

http://community.ratsun.net/topic/18218 ... aturn-alt/
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Laecaon
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Re: how to install a gm 105 amp alt into your datto

Postby Laecaon » Fri Aug 12, 2016 2:46 pm

You can also run a Nissan Quest amp, from the VG30. It is 120amp. You need a V belt pulley, nissan trucks should have that.

Or a 240sx alt at 80-90 amp. I ran a CA18DET alternator on my L18 just fine, it was 80amp.

High amp power definitely makes the car react better. Wipers are faster, and turn signals blink at normal speeds at idle. Heater motor will also blow well at all times.
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DRIVEN
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Re: how to install a gm 105 amp alt into your datto

Postby DRIVEN » Sun Aug 21, 2016 5:45 am

Haha, my car got that same 105A alternator. All I did was swap the engine to get it in.

Noflers, You may find that a Datsun pulley fits the GM Alternator. If not, most any GM pulley would work.
When the only tool you have is a hammer every problem starts to look like a hippy.
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noflers
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Re: how to install a gm 105 amp alt into your datto

Postby noflers » Mon Jan 16, 2017 7:42 am

In the end, I went with a KA alternator, attached to a KA :)
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DRIVEN
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Re: how to install a gm 105 amp alt into your datto

Postby DRIVEN » Mon Jan 16, 2017 8:16 am

See how easy that was? :rofl:
When the only tool you have is a hammer every problem starts to look like a hippy.
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Laecaon
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Re: how to install a gm 105 amp alt into your datto

Postby Laecaon » Mon Jan 16, 2017 9:30 pm

KA alternators work on L series too.

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