The Hot Rod Sled Shop POWER UP Package for the Ski-Doo 800 ETC is a great "best bang for the buck" to go fast and hold on to your cash. It includes the HRSS Stage 2 clutch , the Petschke -D&D Racing Big Mouth Y-pipe with donut and pipe flange, and our Fuel Mod Kit. This package can't be beat for simple bolt on go fast goodies and makes 6-7 hp verified at Dynotech Research. You save a crisp $50 bucks to boot. You may want to purchase y-pipe gaskets separately here on our site (highly recommended as you don't want to do that knuckle buster twice). The clutch kit comes with complete instructions as does the fuel mod.