Pulley Diamater Sizes? (SC Supercharger Kit Post-Installations)
 

Hi Everyone!

In the image attached, I have a Stillen Supercharger Kit installed into the vehicle as you can see.

In the photo, I have circled / highlighted / pointed out 4 different pulleys after the full install was completed.

I was wondering if anyone could be so kind and tell me the diameters of each pulley in the photo / verify my information based on my research.


Green Pulley = ???

Red Pulley = Stillen 8psi stock pulley that came with the kit = ???

Yellow Pulley = 3.2''?

Blue Pulley = 3.2"?

The reason I ask is so that I know when I change both pulleys on the Serpentine Jackshaft side, I would know what sizes to get to make up for any slack by reducing the size of one of them.

Right now, I have purchased a 3.47'' jackshaft supercharger side pulley to replace the yellow one, and a 3.0" supercharger pulley to replace the blue one that is right on the supercharger itself, which makes up about total of 6.47'' (Would be a bit tight because of the extra .07" added but I think I could make it fit?

But the other side for the Jackshaft serpentine side, I know that the 9 psi pulley I purchased is 2.87" which will be replacing the stock 8psi pulley (Red one), but the green pulley (idler pulley) next to that one...I do not know the exact size?

Can anyone help? Thanks, it would be much appreciated! :D

Why do you need to know the size of the idler pulley on the serp belt? There shouldn't ever be a reason to swap it to a different size. Plus, you might want to invest in a $10 digital caliper from Amazon. :tup:

Oh..
I thought I would have to make up for belt slack if I am swapping the 8 psi pulley to a 9 psi pulley size (2.87'').
As in if I am sizing the pulley down some size, wouldn't the belt have extra room again due to downsizing one of the pulleys?
Or do I have this all wrong?

That is also a good investment...never thought of doing that.
I think I will buy one haha.

The Z has a self tensioner.

Never knew that through out all of the information and research I have done. Sweet, that makes me feel a ton better then haha. Now I know I only need to change 3 pulleys then:

- Jackshaft pulley on the serpentine side with this pulley:
https://conceptzperformance.com/stil...13_p_19055.php

- Current 3.2" Jackshaft pulley on Supercharger side with this pulley:
3.47'' SC Jackshaft
https://www.summitracing.com/parts/vor-2a038-300

- 3.0" Supercharger pulley to replace current 3.2"
https://www.summitracing.com/parts/VOR-2A038-347

After I do the 928 Supervortech SCi trim impeller upgrade, complete fuel system upgrade along with Level 10 transmission package upgrade, I think I could pull in some nice numbers with Sebz tuning to top it all off.

Could someone verify that this build would work theoretically?
Thanks I would appreciate it very much :D

Over 320whp