Small alternator pulley

[Photoman]

The battery always seemed low on my 1993 since I don't drive it very far. So I made a new smaller alternator pulley to keep the alternator rpm's up and thus the possibility of putting out more amps at lower engine rpm's. In making the pulley this small, I felt there was not enough metal left to keep the pulley from splitting from the wedging effect of the belts. To leave more metal I had to make the hole that goes over the alternator rotor shaft smaller so the stock nut will not work. This required me to make a special nut to retain the pulley. I have run it for about 5 months and am real happy with the alternator output. A nice thing is this pulley fits either the stock alternator or the upgrade 130 amp Tundra or 150 amp Sequoia alternators.

 

[Photoman]

While I was doing this I decided to try a test to see if the alternator would put out more total amps with my small pulley. I had given my stock alternator from my 1997 cruiser to a fellow member so I did not have a stock alternator to test. I had a Mean Green and a 150 amp Sequoia so I used those. As the pictures show the Mean Green put out 84 amps with the stock pulley, and 91 amps with the small pulley. The 150 amp put out 166 amps with the stock pulley, and 170 amps with the small pulley. Not a whole lot of difference on the top end. These tests were done at a local alternator shop with their machine. The gentlemen at the alternator shop explained that alternator output is not linear but rather a curve that emphasizes output at lower rpm's. That is why my small pulley works so well. It gets the alternator in to its higher potential amp producing range sooner.

 

[Photoman]

150 amp alternator output pictures with stock pulley and small pulley.

 

[Tapage]

damn .. ! Mr. Bill lot's amps .. wonder if I really need it ( hell yeah ! ) are you going to sell those pulleys and nuts ?

 

[Sc0-]

Kool, should be easier to use the OEM sized belts with the Sequoia alternator/Photoman bracket...

 

[OGBeno]

are you going to sell those pulleys and nuts ?

X2 Bill.

When will these be available for consumer purchase?


-onur

 

[Kernal]

Wonder how much this mod bumps the rpms of the alternator? Can the stock belts still be used, enough movement left in the adjusting bolt?

 

[huntir]

Don't tease!!!!! How can we get one!!!!

 

[Otamiway]

X2 Bill.

When will these be available for consumer purchase?


-onur

I am also interested.. good job

 

[sdnative]

Interested in a small pulley to accompany your awesome 150A alt bracket.

 

[Photoman]

OK, I will machine some pulleys and nuts for you folks if you feel it would work out for you. They would be $60.00 plus US shipping; probably $5.90.

With the upgrade 130/150 amp alternators the adjusting bolt I supplied will work and as Sc0 noted this will help fitting the stock belts. With the stock 80 amp alternator a shorter bolt is needed as the stock bolt hits the block when it is adjusted out. I could supply a shorter bolt. I had my wife run the rpm's up for a test. At 4910 crank rpm's the alternator was turning at 14519. This might vary a little as I took a reading between the crank pulley and alternator pulley with my face in there. At almost 5000 rpm's I didn't want to do a fan clutch test with my beard.
To the best of my understanding alternators can take 18000 to 20000 rpm's for short periods. Over several weeks of actual tests the ratio for this pulley works out very close to 3 to 1 which from some of my reading is OK for street use and is not a racing ratio. Someone can correct me if this is any of this is wrong.
Anyone that got a bracket from me in the last couple of months and would want one of these can have free shipping.
Keep in mind the alternator has to be removed to switch these pulleys.

Thanks for looking at this project. If you have any questions post up, PM me or use the photomanfzj80@comcast.net address.

Bill

 

[Ebag333]

Anyone that got a bracket from me in the last couple of months and would want one of these can have free shipping.
Keep in mind the alternator has to be removed to switch these pulleys.

I'm interested!

Good thing I haven't installed it yet.

 

[S.CarolinaFZJ80]

I got your bracket nearly two years ago but haved sourced a 150 amp alternator, yet. Now would be the time to get your pulley and have on hand, so that I can do it all at once.

Count me in for one small pulley! Thanks

 

[IBCRUSN]

Bill,
I'm in!!! I've been very happy with the bracket and the 150A Sequoia alt I installed a few years back. This would be fantastic for low RPM trail rides, winching and running other electronics. I'll shoot you a PM and we'll go from there.

 

[DMOZ]

This is great, Bill. Thanks for taking the time to make and test.

Happy owner of your bracket and will PM you about the pulley.

 

[pgmatt]

I'm down for one! Still making the brackets also?

 

[Photoman]

I'm interested!

Good thing I haven't installed it yet.

Lol procrastinator

I'm down for one! Still making the brackets also?

I can fix you up with a bracket if you want one. Tomorrow (I hope) I am going to powder coat some of the adjustment arms for the brackets.
PM me or use the above email.

I am shipping the first pulleys tomorrow.

Thanks everyone.

Bill

 

[Otamiway]

I am prolly one of the biggest procrastinators.. from 3/10... I would like one. PM Sent

 

[Photoman]

I sent the first pulleys out this morning and discovered the shipping price is off a little. For those that already have paid you hit the lottery j/k.
The total price for the pulley and shipping is now $66.10. For now, I can't seem to edit my post above with the price.

Another note: I decided to include a shorter stainless adjusting bolt in with every pulley whether it is for the stock 80 amp alternator or the upgrade 130/150 amp alternators. The bolt with the upgrade bracket would work but just stick out further. The couple of bucks for the bolt is not work the different packaging hassle.

Bill

 

[NLXTACY]

Perfect timing. My engine is being rebuilt as is the 150amp alt I have now. I will take one!!!

Thanks Bill