double v-belt pulley on 130amp alternator - Vintage Mustang Forums

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post #1 of 10 (permalink) Old 08-15-2015, 03:51 PM Thread Starter
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double v-belt pulley on 130amp alternator

Hi Everyone,

I am trying to run a double v-belt pulley on a 130amp alternator. I have power steering and a 3 groove crank pulley. Does anyone have pics of running a similar setup? It looks like the only way to do that is by having a very long belt connecting the power steering pulley and 2nd groove of the alternator v-belt pulley.

On another note, is there a way to tell if my drive shaft has the rubber dampner inside it and is able to be shortened?

Thanks for the help!

Last edited by Stang Guy; 08-15-2015 at 03:52 PM. Reason: added pictures
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post #2 of 10 (permalink) Old 08-15-2015, 04:02 PM Thread Starter
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Here are pictures of the setup.
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File Type: jpg IMG_5083.jpg (89.6 KB, 63 views)
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post #3 of 10 (permalink) Old 08-15-2015, 05:21 PM
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Usually you would run a single or double belt on the alternator/water pump /crank and another belt on crank/power steering or crank/water pump/power steering .

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post #4 of 10 (permalink) Old 08-16-2015, 01:26 AM
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I've fought with that in the past with little luck, depending on the vehicle. On my '67 I've found it practical to only run a single sheave with my current setup. Not being a driver, I haven't had it for real world testing. Depending on setup, some people have had belt squeal. If I get that then the first thing I will do is try a "289 HiPo" alternator pulley. The larger diameter slows the rotation a bit but happily 3G's deal with low RPM operation without really high demand quite well. The point of swapping to a HiPo pulley is to give the belt more surface area to contact. More area=less slip=less squeal. The goal being no squeal. Without actually doing the math, I'd guess the contact area of HiPo pulley to be quite a bit more than the stock diameter but maybe not as much as a double sheave.
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post #5 of 10 (permalink) Old 08-16-2015, 04:54 AM
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Since i have my 3G alternator i have a squeling and belt eating problem with ac and electric fan on.
With a double pulley on the alternator and longer ps belt the problem is gone.

With out ac, electric fan and other high current parts you can try a bigger diameter for the alternator pulley. Like GypsyR said.

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post #6 of 10 (permalink) Old 08-17-2015, 02:36 AM Thread Starter
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Thank you everyone for the pictures and help! This definitely helps.

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post #7 of 10 (permalink) Old 08-17-2015, 03:54 AM
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You can run a double pulley on the alt but i don't know why. I have always run a single groove pulley with a stock alt and have ac with never a problem with belt squeal. Wii soon be switching to a 135 a 3g and will still keep the single groove pulley. Though on my preset vehicle I run a hipo alt pulley to slow down the alt rpms because of the larger crank pulley.
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post #8 of 10 (permalink) Old 05-18-2017, 02:24 PM
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Similar to Markus, I have a long belt that runs around the crank, power steering, over the water pump, and around the 3G alt pulley. Then a shorter belt just going around the crank, water pump, and the second groove of the 3G alt pulley. It can be difficult to get the tension on both belts exactly the same to avoid belt squeal, but it can certainly be done. I run this setup on the '67 daily driver and it's totally fine with no squeal.

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post #9 of 10 (permalink) Old 05-18-2017, 04:46 PM
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post #10 of 10 (permalink) Old 05-20-2017, 02:58 AM
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