ZZP vs. A.N.S.I Groove Design

Posted by Alex Darmos on

A.N.S.I. is an acronym for American National Standard Institute, which is an organization that promotes standards of conformity in the manufacturing industry. The A.N.S.I. has a published standard for V-groove belt and pulley design. These are simply the standards of conformity by which belt and pulley manufacturers can be assured of mutual product compatibility. When we at ZZP designed our pulley system, we were first and foremost concerned with grip, reliability and weight. We looked at the stock OEM pulley, which has an A.N.S.I. groove design, to see if we could improve on it. We made these observations:
  1. The tall rib and tight radius on the A.N.S.I. design would allow the rib to bottom out into the belt groove as the belt wore. This bottoming would prevent the belt from seating tightly into the V-groove and could result in belt slip. In the ZZP design we truncated the tops of the ribs to prevent rib bottoming, resulting in a consistent grip as the belt wears. (see diagram)
  2. The A.N.S.I. design groove is much deeper than what is required to clear the bottom of the belt rib. This deep groove contributes nothing to performance and actually weakens the pulley. The ZZP pulley uses a larger radius on the bottom of the groove, which results in a shallower groove and a stronger pulley.
  3. Lastly we narrowed the groove V-angle slightly which increased grip on the sides of the belt ribs.
Some of our competitors have bragged about their A.N.S.I. standard pulleys and criticized the fact that the ZZP pulleys didn’t meet the A.N.S.I. specs. We believe that they didn’t do their homework. ZZP has sold over 1000 pulleys in the 3800 market. Our reputation for performance and reliability speaks for itself. Currently the highest HP Gen 3 M90, Gen 5 M90, non-intercooled M90 all use ZZP pulleys on the supercharger. The highest supercharged Grand Prix in our market runs over 20 pounds of boost with his Novi 2000 and makes nearly 500WHP using a ZZP pulley. ZZP built a test rig for checking belt grip on a given pulley, in response to a vicious attack filled with lies and misleading information that was released by a competitor who blatantly copied our pulley system. The testing equipment was actually quite simple. We used a mill with digital readout to adjust belt tension, and a snap-on digital torque wrench to measure point of slip. With the torque wrench attached to a pulley in the system, we can measure how much torque it will take before it slips on the belt. The ZZP pulleys outperformed the A.N.S.I pulleys by a considerable margin.

ZZP and A.N.S.I v-groove belt comparison 

ZZP and A.N.S.I v-groove belt comparison



As a side benefit from the testing, we learned that not all belts performed equally. The Gatorback belts did not perform well in the belt grip testing. This leads us to believe they are designed to be a quiet, long lasting belt, for the accessory system only. For the supercharger, the Gates premium belts outperformed the other brands tested.