Edelbrock SC Smallest Pulley

[Nawar]

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]

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

[CSG Mike]

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

Yes, you need a smaller belt.

[Nawar]

Originally Posted by CSG Mike

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

Yes, you need a smaller belt.

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

[CSG Mike]

Originally Posted by Nawar

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]

Originally Posted by CSG Mike

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]

Originally Posted by Nawar

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]

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]

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]

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]

Originally Posted by GPhilly

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]

Originally Posted by CSG Mike

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.....