For SB Chevy Aluminum Crankshaft Pulley 2 Groove LWP Long Water Pump SBC 350 Crank Fits All SB Chevy Engines When Using A Long Water Pump Fits SB Chevy 265 283 305 327 350 383 400 Using A Long Water Pump Pulley Diameter Is 6 9/16" Pulley Is 2 3/4" Tall Center Hole Is 1 1/8"