So, finally decide which direction to go with my High Output alternator swap/build.

After careful deliberation and research I have decided to keep the stock alternator with a few celebrated changes.



Got the new parts in from Boyle Future Technology in Auburn, CA.

$138 shipped - 90 amp stator, new Heavy Duty rectifier, bearings, and brushes.

Supposedly good for 90 amps at idle (if I remember correctly) and between 130-140 amps above idle.

Can't quite figure out where this part fits though...




Just kidding. But anyway, My tired old alternator puts out about 12.15 volts at idle with a 40 amp load, so we'll see what the difference is when I'm finished.

I am still working 10's, so we'll see when I have time to tackle this...

 

Dang it! Its apparently the same thing I'm building. Except that you don't have to build it....

Oh well.

 

Ok, some pics...













You can see what I removed, not too bad looking for having 217,000 miles on it. I started tearing it down, everything went smoothly. You can see there isn't much left of the brushes and the rectifier is caked with some factory spray that can't be good for heat dispersion.

 

You can see the stator leads sticking out through the case with rubber sleeves.
You'll need these later.

Removal of the case was simple, once the nuts were off of the bolts, some gentle tapping with a center punch and a hammer got everything loose. A small pulley puller would help remove the smaller bearing off of the rotor shaft, but I managed with a couple of screwdrivers.

 

Reassembly was pretty easy, the biggest hassle was getting the leads to fit in the place of the factory ones. These are twice the size of the originals, so the largest lead location on the case had to be opened up with a dremel so it wouldn't rub.

http://www.4x4wire.com/toyota/tech/alternator/

You can see the difference between the stators and the rectifiers, I cleaned off a couple of the original diodes so you can see the difference in size. This matters greatly when it comes to the heat it can handle. There are a lot of rebuilt "High Output" units that only come with the 90 amp stator with nothing else upgraded.

The final outcome is great. I could only get a 40 amp load on it when I took the pic, but at 40 amps, you can see the voltage is awesome!
In fact that may be why the amperage was lower with the same load...

 

My amplifiers and compressor are very happy.

 

Haven't had any issues. I don't remember how long ago that was, the OP will have a date on it....

Still makes good power.

 

Optima Yellow Top. Going on 7 years now. Same battery.

 

140 amps at idle? Most HO alternators are rated at peak current, kinda like crappy amplifiers are rated at peak wattage.

 

If I understand the theory correctly, the Wye would create more voltage at lower RPM's allowing it to be more usable for normal engine use. The Delta generator windings would require higher RPM to start charging, but (if the windings are of adequate size) would potentially create higher peak amperage.
If you used a smaller pulley, like you said, you could get that voltage at a lower engine speed, but will create more load on the engine at the same output until you overcame the current capabilities of the Wye windings.