Mini 6.78lbs 102mm Denso Alternator install/pics/testing

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autoxcuda

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I just installed a Nippondenso 102mm alternator with ~50 amp advertised in my Barracuda small block with aluminum 70-up water pump and 69 down cast iron water pump.

I tested it all last week on the current small block motor in my car with cast iron water pump (69-down). That was a temporary deal and the belt was about a 1/2 grove (1/4") off line. If I bent the original alternator bracket back offset that amount, I would be good to go.

BTW in case you wanted to know...

THIS THING WORKS AWESOME!

I got the 102mm mini Nippondenso single V-groove pulley from like a Chevy Sprint 1985-88 in the junkyard. But the part number 31400-83010 corresponds to a Suzuki Samurai 1.3L 1986-1989, Chevy Sprint 85-88, Suzuki Swift 84-89 and possibly others. It seems to come in 45, 55, 60 amp versions from rebuilders. Mine tested fine at the parts store. It is the same physically as powermaster p/n 8122/8128 6.78 lbs. 102 mm. ( http://www.powermastermotorsports.co...ternators.html ) The stock ones are not one wire like the powermaster ones. But they have an internal regulator.

The alternator bolt holes that go to the head attachment need to be drilled out a little to accept the larger bolt.

I even used the existing brackets. But it was just a mock up on this 64-69 SB cast iron water pump housing. The alternator pulley was about a half to one groove off. Ok for driving around a little and testing, but not right for a permanent setup.

One way to correct the fitment issue would be to remove material of the backside on the front alternator ear. Or better, if I bent the orginal alternator bracket back offset between 1/4" to 1/2" amount, I would be good to go. Take the origal alternator adjuster bracket and shorten the engine side to fit.

For the 70- up aluminum water pump housing the fitment was even easier. We just cut down spacers to fit from HD sway bar end link kits of all things.

For the wiring just connect the input and output of the single field regualtor that goes to the back of the orginal alternator. I connected that to the "I" or “IG” Ingnition port of the Denso alternator. Same green wire that went to my alternator before. Then for the "S" sense port, I ran a jumper directly to the battery. Then the big output lug to the harness bolted on...

DONE!

Drove the car and night, NO dimming at idle. I mean nothing. Even with every electrical item I had turned on. I even put it in gear, revved it quick and jumped off the thottle so it would rev down to 400 rpm. Just an ever so hint of a dim lugged down to 400 rpm. With the previous alternator, the night before I could hardly see my instrument lights at idle! This Denso thing is AWESOME.

Alternator guage is still hooked up and didn't falter a bit. The voltage in the battery was 12.2v non running. Running it was 13.8 then would slowly climb to 14.1-2. When you put all the electrical draw on it, it wouldn't even change a tenth of a volt!

70-up aluminum water pump fitment in first two pictures.
 

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Awsome! Good to hear it works great. I just bought one off of ebay that has been internally wired for 1 wire hook up, and bought a set of brackets from Hughes Engines for a direct bolt in on my 73 Dart Sport bracket racer. I can't wait to try it out.
 
Awsome! Good to hear it works great. I just bought one off of ebay that has been internally wired for 1 wire hook up, and bought a set of brackets from Hughes Engines for a direct bolt in on my 73 Dart Sport bracket racer. I can't wait to try it out.

Could you post links to that ebay ad and the Hughes brackets?
 
Hmm,I wonder how it would work out in a big block app?
 

That seems like a nice setup. $74 and you get one wire hookup! The regular 86 Suzuki Samurai alternator rebuilds at Rock Auto are $127 without core: http://www.rockauto.com/catalog/moreinfo.php?pk=513270 And that's the 6.78 lbs one like I have that weighs more.

I think it might be possible to rig you own alternator brackets with that other one wire alternator too. But those ARengineering brackets are nice, clean looking, and have a better angle to the adjustment slot that I have. Whatever you budget allows.
 
I am doing the wiring on my 67 cuda.I used a altenator from a dodge truck.135 amp mini alt.I am hooking it up the same way but I am going to use electrinc reg.The guy sells them on moparts for 28.00. <ark
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I am doing the wiring on my 67 cuda.I used a altenator from a dodge truck.135 amp mini alt.I am hooking it up the same way but I am going to use electrinc reg.The guy sells them on moparts for 28.00. <ark
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Do those Dodge truck alternators have an external regulator? These Denso alternators already have a regulator built into the back of them.
 
this is a Nippon that been on my demon for about 10 years, went to the part store and asked for a 60 amp 1989 Toyota 4- runner alt, then used the HD A/C alt bracket that mounts to the head, traced the ark of the low mount hole on the alt, then cut and weld the bracket with some flat stock to make the new slot. As for the triangle mount copied the original but left out the offset, all for about $40 !! been working great for all these years, holds steady at 14.4v with all my acc on including elec fan, and fuel pump
 

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BTW, that alt mount is the ticket for fast/ hi reving engines!! the alt doesn't flex a hair.
 
AR Engineering also makes brackets to fit the Toyota 4 Runner Alt. to SBM, also $50 for the set!
 
Mancini racing offers the Denso conversion bracket for $49 works very well on small block. Uses Toyota 92 4 Runner 4cyl. 60 amp. a-zone $85 reman.Will post pics soon.
Peace...
 
I see thee are lots of different amp ratings for these alts. Anything from 40 to 120!! How much alt is really needed? Lets say you are in a high demand situation,hi powered ign,elec fans,etc and are making passes at the track. In order to not kill the batt,Im thinking 80 amps would be enough?
 
my 60amp worked fine on the street at night with elec fan and pump. it holds at idle 14.4 volts not like the lazy oe mopar ones. I think if you start to go over 60 amps you may have to upgrade the wire size through out to be safe.
 
My brackets arrived today from Hughes Engines. I laid a $20 beside the Alt. just to see how small they actually are.
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Do those Dodge truck alternators have an external regulator? These Denso alternators already have a regulator built into the back of them.

If you are referring to the late model efi alternators, they are regulated by the PCM, so a carbed setup requires the external regulator.
 
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