VMP 15% OD Balancer Pulley for 2011+ 5.0 Supercharged VMP/Roush/Whipple
VMP's 15% overdrive 10-rib "AC pulley" for the ATI balancer (fits ATI PN: 918047 or 918047N) adds 3 lb of boost and allows for future 10-rib conversion.
You need an SFI balancer anyways, our pulley coupled with an ATI balancer gets you more boost! The 25% OD will require trimming of your oil pan and relocation of your tensioner.
It's referred to as the AC pulley because it normally drives only the AC compressor, but on VMP, Roush, and Whipple 2.3L supercharged Coyotes it also drives the supercharger. This was done to load the crank shaft as close to the front main bearing as possible and make the SC belt as short as possible.
Works with both 8 and 10 rib systems (8-rib belt uses middle eight ribs).
As part of VMP's 10-rib conversion system for the Coyote, we've designed an overdrive pulley that bolts in place of the "AC pulley" on the ATI balancer. These positive displacement supercharger systems use the rear shiv for best possible crank loading.
15% OD = +3psi boost increase
Full 10-rib conversion recommended when running over 16psi.