Save your money and get the ATI it is totally worth it as it will balance better and is lighter, and fits every time.
https://www.waymotorworks.com/super-...ulley-r53.html

If you have the PRW the S one is stock size, you are fine to just install a 17% pulley
https://www.waymotorworks.com/wmw-pulley-package.html

 

ordered the ATI 2% from you earlier today. This time next week I’m hoping to have it installed with a little more boost. I might be able to test out before/after boost levels as well. Waiting on a WiFi obd2 connector.

 

It will ship out later today.

Would be nice if you could dyno it before and after. But the other nice thing is you'll find the A/C will work just a hair better when you are sitting at idle.

 

The dyno before and after would be cool.

I’m changing out the belt, tensioner, and doing a timing chain and guide replacement. It seems it might be possible the car would dyno higher after all those changes even if I didn’t do the 2%. But maybe not. Not sure if any of the things I’m replacing are really robbing any power.

I used to dyno baseline and then after doing mods to some of my previous cars, but just seems like too much of a waste of money at this point.

 

What percent SC pulley do you have and what size belt did you get to run with the 2% ATI?

 

I have the stock JCW pulley which I think is 11% smaller than stock I believe.

Since I’m replacing the damper anyway, I went with the 2% size so I can get a little more boost, without needing a specific JCW pulley puller tool and new supercharger pulley.

I was told by Way that the stock JCW size belt is what I need for my setup. I’m assuming the 2% ATI doesn’t make too much of a difference for belt size.

 

Thanks, I have a 15% with a 2% waiting on the shelf. The info I’ve found for this has been inconsistent so I’ve been trying to find someone actually running this combo to find out what belt size works. Some sites list a different size with a 2%, and some list the same size as the SC pulley alone.

 

If I were you, I would contact WMW or maybe they’ll chime in here, and get the belt from them, unless you figured out that you have what you need already.