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-   -   Edelbrock SC Smallest Pulley (https://www.ft86club.com/forums/showthread.php?t=136722)

Nawar 09-07-2019 07:25 AM

Edelbrock SC Smallest Pulley
 
Hey guys, I have searched forever to find a pulley smaller than 3.00" and i found on that is 2.65" but not sure if it fits our supercharger, can someone point me where i can buy a Pulley smaller than 3.00" and if so Do i need to change my Engine belt to accommodate the smaller pulley?

Cheers!

86TOYO2k17 09-07-2019 10:41 AM

https://www.edelbrock.com/2-75-6-rib...tem-15823.html

CSG Mike 09-07-2019 12:04 PM

https://www.edelbrock.com/2-65-6-rib...tem-15814.html

Yes, you need a smaller belt.

Nawar 09-18-2019 11:27 AM

Quote:

Originally Posted by CSG Mike (Post 3255090)

Is it possible to send me a link of the smaller belt?
Cheers!

CSG Mike 09-18-2019 03:50 PM

Quote:

Originally Posted by Nawar (Post 3258674)
Is it possible to send me a link of the smaller belt?
Cheers!

Your local auto part store will have it. Edelbrock themselves do not sell the belt.

Nawar 09-27-2019 07:14 AM

Quote:

Originally Posted by CSG Mike (Post 3258765)
Your local auto part store will have it. Edelbrock themselves do not sell the belt.

Sadly All the auto stores next to me never heard of the brz/86

anyways i dont mind buying one from Amazon or anywhere else.

The Pulley I bought is the 2.75 Inch one, so any help would be appreciated.

DeliciousTuning 09-27-2019 10:56 PM

Quote:

Originally Posted by Nawar (Post 3261697)
Sadly All the auto stores next to me never heard of the brz/86

anyways i dont mind buying one from Amazon or anywhere else.

The Pulley I bought is the 2.75 Inch one, so any help would be appreciated.

Just check your belt for a part number and then just get a small version of it. You can all up an autopart store and they can tell you what are the part numbers for small belts. I would go about 1.5 - 2 inches smaller in length.

Irace86.2.0 09-28-2019 12:58 PM

Just for reference, the circumference of a 3” pulley is pi x diameter or 3.14 x 3” or 9.42” and the 2.75” pulley is 3.14 x 2.75 or 8.64”.

Say you were going to string a rope of almost infinite distance apart like say from our solar system to the other side of the universe, and then you decided to lift this perfectly straight rope by the distance of the 3” pulley then you swapped to a 2.75” pulley. The difference in length of the rope would be practically zero, but not zero.

Next, say you wrapped the pulleys completely with the rope, so the incoming and outgoing lines of the rope touch. Then the difference in distance around the pulleys is the circumference or 0.78”.

The routing diagram of the belt around the supercharger pulley to the other pulleys is neither so flat as to approximate infinity, nor is it so extreme as to approximate circumferential. This means that the new belt length will be between 0” and 0.78” shorter, yet considering the diagram angles look to wrap about three quarters of the pulley then it’ll be close to 0.6” shorter. Therefore, if your belt was perfectly taught previously with the 3” pulley then buying a belt that is around 0.6” shorter would be ideal. If it was already loose then Bill’s suggestion of 1.5-2” could be fine.

Irace86.2.0 09-28-2019 03:15 PM

The standard belt for the 3.25” pulley is 99.5”.

3.25” x 3.14 is 10.21”, and the 2.75” pulley is 8.64”, so that is a difference of 1.56” and considering the power, a tight belt is ideal, which gives more credence to what Bill said when he suggested you go with 1.5-2” shorter. Again, that is if you have the stock belt already.

Regardless, the goal is to find a belt between 97.5-98”.

I would suggest getting a six rib belt of the Gatorback or poly-v variety, so you don’t get belt squeal. These are the types of belts included in the supercharger kits.

https://static1.squarespace.com/stat..._FA_LowRes.pdf

https://static1.squarespace.com/stat...heet_v2_HR.pdf

GPhilly 04-19-2022 04:50 PM

What's the WHP increase with the smallest pulley? I'm ordering my kit soon and was planning on asking for a 3" but I'm curious on other sizes.

CSG Mike 04-27-2022 09:14 PM

Quote:

Originally Posted by GPhilly (Post 3518028)
What's the WHP increase with the smallest pulley? I'm ordering my kit soon and was planning on asking for a 3" but I'm curious on other sizes.

Depends on the rest of your setup. I wouldn't recommend a smaller pulley in any way shape or form without a built engine.

GPhilly 04-29-2022 04:51 PM

Quote:

Originally Posted by CSG Mike (Post 3519584)
Depends on the rest of your setup. I wouldn't recommend a smaller pulley in any way shape or form without a built engine.


Good to know. I'll stick with the stock SC pulley for now. I do not have built internals... yet.....


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