More boost...

Time to add more boost to my built motor so here is what I know:

Stock pulley:
3.3" diameter
0.64" keyed shaft (not press fit)
0.4" offset
6 rib
nut torque spec: 45 ft-lbs
Magnuson part number: 58-90-06-033

Stock Cosworth belt:
Gates Micro V-AT K061040= 6rib 104"

The supercharger is rated at 16000 rpm so I cant exceed that.
I decided to go with the cheapest pulley I could find for testing purposes as I could not find any formula that would determine boost output. I went with the smallest readily available pulley which wouldn't overspin the blower. The charts to the side are from Magnusons web site for this blower.










I bought a 2.8" pulley from PulleyBoys.com Install wasn't too bad, there is only one bolt to remove (do this before you loosen belt tension or use an impact wrench)then i used a cheap pulley puller ($5) from AutoZone to pull the pulley off. They say that a puller is not needed but as it was my crappy puller barely was strong enough to get it off, so don't believe the hype. I put the new pulley on with some anti-sieze lube and torqued the nut.

The ne w smaller pulley required a new shorter belt so I got a Gates Micro V-AT 061031= 6rib 103.625"OD. This is for sure the shortest belt one could go with for this app as it was a tight install but that is what I was looking for.

so here is the pudding...14psi! at a little under 15k rpm at redline. NICE!