I need to know what kind of measurements you get when measuring the outside diameter of a JCW pulley and a stock pulley.

I am unsure if the dealer that did the JCW upgrade orgionally actually changed the supercharger to the right one. I am going to remeasure tonight, but i was wondering what measurement was normal. I found pulley measurements, but don't know how they are measured.
What actual measurement do you get from edge to edge on the outside face of the pulleys not including the belt?

Thanks....I need to know before i drive almost 6 hours to the pulley party.

 

There are several threads with multiple measurements here. Do a search on JCW pulley size

Much of it is right here in a sticky https://www.northamericanmotoring.co...ad.php?t=33923

 

I have measurements, but I need to know if I am measuring right? it is just the outside edges? do I measure just inside the lip where the belt lays? I am sooo lost....

 

Are you replacing the supercharger pulley or fitting an oversize crank pulley?

 

The supercharger pulley. My husband wanted to do a 15%, but when we got to reading more, found out that the JCW already have a reduction. But we are having a hard time figuring out if it is the right pulley. It looks much larger than the 15% reduction that his friend has on his mini. I did notice that the mini pulleys look like they have more of a ridge around the outside than the aftermarket ones do. That would make it look bigger and measure different.

Any ideas?

 

not the ridge that keeps it from wandering off. Stock pulley measures 2.588" plus or minus a bit.... I used a cheap caliper. A 15% should measure about 2.2", JCW a bit larger than that. If you didn't get a new SC, time to ***** up a storm!

Matt

 

Thanks. I think it is a reduced pulley. When I measure all the way from edge to edge (including the ridge) it still doesn't hit 2.58 inches. I am pretty sure it is smaller.

 

Finally found this thread in a search. Something that gave numbers. Sometimes the search feature can be a booger.

From the other thread.

I need to get some calipers to accuratly measure but from my measurments so far, against a stock pulley I have, they are identical. BTW, I have a factory JCW kit. The reason I checked is because of performance concerns based on my previous slightly modded MCS.