I'm running the 102mm with ~50 amp advertised in my Barracuda small block with aluminum 70-up 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. 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.
69-down cast iron water pump fitment.
Temporary mockup. Not permenent fitment or wiring
