SB Chevy 421 Stock Car Engine, Dart SHP Block, Dart heads, Flat tappet solid lifter camshaft, Eagle crank and rods, Mahle flat top pistons 13.5:1, world intake, Holley 4412 500cfm 2bbl carb. Engine produced 499 HP at 6400 RPM and 507 Torque at 4600 RPM.. Competition Engines, Brookings, SD, Call toll free 800-341-1528 or 605-692-1697 to start your custom engine build….