Fixed Vacuum Pump Crank Pulleys
Works with the GZ Alternator Pulley
The GZ Motorsports line of fixed crank pulleys are all designed for driving a vacuum pump with a standard V-Belt. The pulley OD sizes vary by model which are listed on the Specifications tab. If you want to add an alternator pulley, the GZMS CP99 5" Dia Crank Pulley [image] is designed to bolt to the to either the front, or backside of this Fixed Pulley (depending on model) allowing you to run both the Alternator and Vacuum Pump from the same assembly. All models have a 1/8" dia hole on the back for a roll pin (included) that engages the crank keyway to prevent rotation.
Specifications
All Fixed Crank Pulleys are made of 6061 T6 Aluminum.
CP100A Small Block Chevy
- Single Bolt Style, 7/16" Through Crank Bolt Hole
- Mounting bolts for CP99 5" Alternator Pulley
- Single Groove 3.5" OD Pulley for driving Vacuum Pump
- Belt Centerline 3.87" from balancer face.
- 4.37" Overall Depth, plus .1 lip that goes into balancer bore
CP101A Big Block Chevy
- Single Bolt Style, 1/2" Through Crank Bolt Hole
- Mounting bolts for CP99 5" Alternator Pulley
- Single Groove 3.5" OD Pulley for driving Vacuum Pump
- Belt Centerline 4.37" from balancer face
- 4.87" Overall Depth
CP103A Small Block Ford
- Single Bolt Style, 5/8" Through Crank Bolt Hole
- Mounting bolts for CP99 5" Alternator Pulley
- Single Groove 3.5" OD Pulley for driving Vacuum Pump
- Belt Centerline 3.25" from balancer face
- 3.75" Overall Depth
CP104 Big Block Ford
- Four Bolt Ford Style
- Double Groove 4.5" OD Pulleys for driving Vacuum Pump & Alternator
- Belts located in approximately stock locations
- Total Depth 2.5"
CP107A Small and Big Block Mopar
- Single Bolt Style, 3/4" Through Crank Bolt Hole
- Mounting bolts for CP99 5" Alternator Pulley
- Single Groove 3.5" OD Pulley for driving Vacuum Pump
- Belt Centerline 3.5" from balancer face
- 4.0" Overall Depth
Pulley Ratio & RPM Calculator
GZ Motorsports Vacuum Pumps should avoid shaft RPM's in excess of 6000 RPM Pump Speed (not engine speed). The Formula used is Vacuum Pump RPM = Engine RPM x Crank Pulley Teeth/Vacuum Pump Pulley Teeth