GripTec is a patented process developed by Z-Industries and applied to pulleys in order to reduce belt slip.
It's actually a family of processes, GripTec Micro - a micro machining process, and GripTec Weld - an additive micro welding process.
We've been working with Z-Industries to improve the characteristics of our double alternator pulley (which drives the Supercharger), in order to reduce belt slip.
Belt slip isn't always noticeable but it is generally present and can result in 1-2psi loss of boost even in low boost setups. Our aim is to reduce this as much possible. We'll soon be looking at also replacing the pulley on the Supercharger itself with a GripTec one for further improvements in performance.
This is a link to a pretty cool Coyote engine build video, they use quite a few aftermarket parts but noticeably a Z-Industries GripTec pulley which really helps to reduce the belt slip that they were experiencing and therefore increase horsepower to over 1100 and a whopping 822 lb-ft of torque - and we all know that torque is king!