This is a zz502 big block that was bought fully assembled from Chevy. This 100% stock crate motor comes complete oil pan to carb. It's a victor jr. Intake, holly 830 cfm carb and it comes with msd/ coil built in distributor. Motor has 11000 documented miles. Motor is in perfect condition runs and still in car to test drive. Call with any questions 6316808040 nick.