Harley Davidson Shovelhead "Big Bore" Performance 3-5/8" Shovelhead Stroker Kit. This Kit is great for people on a budget. It performs just as well as many of the other high end Brand name kits but will not burn a hole in your pocket. If you shovelhead is tired and old, refresh it with a Performance oriented Stroker Kit. These kits include 3-5/8" Bore Cylinders, Furnished with Pistons, wrings, Pins, & Lock's. Displacement of your shovelhead engine will depend on what size Flywheels you are using. For Performance Shovelhead Flywheels I will ONLY Recomend Truett & Osborn Which we use in all our stroker engines from Harley JD upt to The new Evolution.