Used Circle Track 421 SBC Steel Engine . #511 4-Bolt Block,Steel Crank ,H-Beam rods ,Forged Dome pistons ,230cc Dart heads ,Solid Roller Cam,Roller Rocker Arms ,Stud Girdle , Wilson CNC ported intake . Will need freshened. Ran great before pulled ,but is close to laps on Interval. Ran in Pro Stock .