The Vortech belt for AP1 is 4060510 (6PK1295) It is 51" (1295cm) and used with 5" Vortech factory supplied pulley. Vortech belt for AP2 is 4060500 used with the 4-1/2" pulley.

Belts for Vortech:
4060510
4060505 (6PK1285) 50.5"
4060500 (6PK1270) 50" used with 4 to 4-1/2+ inch pulley May stretch and become loose on 3.8"
4060495 (6PK1255) 49.5" used with 3.5-4.0 inch
4060490 (6PK1245) 49" used with 3.0 to 3.4 inch


COMPTECH SUPERCHARGERS

For Comptech:
4060400 Standard AP1
4060395 4.25inch
4060390 4.0inch(7#)
4060385 3.5 3.35inch
4060380 3.25inch
4060370 3.0 inch

belt for removing AC: 4060450 (6PK1145) 45"

Factory belt: 4060578 (6PK1480) 57.8

Gatorbacks are available in all these sizes.
Chart modified 4/16/06, 7/4/06, 11/02/06 Thanks to Modifry, FF2Skip
Summitracing.com and others are good sources for Gatorbacks. Some sizes are not in stock and may take additional time to obtain. I suggest you plan ahead.
Additional reading on pulleys: https://www.s2ki.com/forums/index.ph...pic=380286&hl=

A good source for pulleys with a non-skip lip is ASP Racing You must call them since our pulleys are not listed on the internet.

Reichard Racing makes a pulley that bites well if you are having pulley slip issues.

 

Thanks for this. I've put this thread into the FAQs.

 

Will:
4060490 (6PK1245) 49" used with 4 inch pulley

the belt above work with a 3.8" pulley?

 

3.8 inches is right at the limit. Let us know how it goes.

 

man i have a 3.5 pulley but i don't know what belt to get (comptech)

 

The Comptech SC uses shorter belts. Unless I'm mistaken the stock is 40 inch and the one I'using with my 4 inch pulley is 39.

You can roughly work out the difference. If I'm using a 39 with a 4" then the Pi * R (6.3") is the approximate length of the belt going around the pulley. That is because the circumference of the pulley is 2 * Pi * R and we're assuming the belt covers 50% of the circumference and R is D/2.

So if you do the same maths for a 3.5" pulley only 5.5" is around the pulley. The difference is 0.8 if an inch. So I would recommend a 38" belt and I'm willing to bet the part number is something like:

4060380 (6PK0965)

 

does this sound right for the 3.5 pully i read this somewhere

The brand is Dayco and the part#560390

 

Well call me psychic but I'd say that was a 39" belt. Assuming you have a Comptech SC that will probably fit. Your tensioner will just be a bit further in than mine.

 

huh, i am comptech?

 

The 'psychic' bit referred to my inate ability to determine the belt length from the part number.

My calculation suggests 38", someone has recommended 39". Either way it's pretty close. I'd say try the 38 and if it is too small, exchange for a 39".