how big is a stock pulley?

Quick answer: on what?

Please put your year car and trim level in your signature. We would assume if you are asking about a pulley you are talking supercharged.

On a side note...the pulley size on the tricycle raced in MN last weekend was a sweet 2.56, which gave Nate the advantage on the hole shot.

92/3 is 2.5"
94/5 2.8 or so i believe
96-current = 3.8.

WOW, those pulley sizes went up over the years. Was this to cut down on KR or for some other reason?

No, it was because of different superchargers. The 92-93 had an M62, the 94-95 had a later gen M62, and the 96-present has an M90.

Also, when a blower has a greater efficiency, it needs less rpms to make the same boost. I think the 94/95 had a larger inlet and teflon coated rotors which improved it from 92/93? But yeah like Sol said the 96+ is different all together.

uh huh...like always Ive been educated. Thanks guys

Actually not teflon. They're epoxy coated. But otherwise dead on.

Hmmm I thought you said before they were teflon

I thought they were, as did everyone else. i know better now. Teflon would be a waste, as they never touch. It'* an epoxy coat to seal the aluminum, and decrease the clearance between the rotors for higher efficiency.