The 8-Rib Drive Upgrade package is a great addition for those looking to take their 2018-2020 Mustang GTs to higher boost numbers and even higher horsepower. More belt contact surface area means more grip, and no slip! 8-rib design allows for maximum belt traction and stability Maintains the factory automatic drive belt tensioner Compatible with all 2018-2020 Vortech and Paxton Mustang GT systems Aftermarket 8-Rib damper pulley not included and must be sourced separately Included Components 2A038-347 supercharger pulley (3.47" diameter) and appropriate belt (2A048-100) All necessary hardware and precision machined spacers Replacement alternator pulley, water pump pulley, and idlers Optional supercharger pulleys: 2A038-333 / -315 / -312 / -300 / -295 / -285 / -280 / -275 / -270 Misc. Notes Custom ECM programming and fuel / ignition system upgrades will be required. This applies any time the supercharger drive pulley ratio is changed to any size other than what was originally supplied in the complete supercharger kit. Supercharger pulley removal may reduce or void the supercharger unit warranty. Pulley diameter changes: Careful size selection is mandatory for proper engine and supercharger longevity. Contact Vortech Tech Support for assistance with impeller speed calculations if necessary. This upgrade is not emissions legal for street use A Vortech BV-57 or Mondo compressor bypass valve is required for applications producing more than 13 psig. Special tools required: 17mm hex impact driver (OEM alternator pulley removal) Crankshaft damper puller / installer tool