350 pulled out of my 1974 corvette was original engine had been rebuilt at one time . Mileage is unnone does need a new cam, lifters,etc. Did not knock or smoke when it was in the car. Mileage on the car was 126,000 so your guess is as good as mine on when it was rebuilt. Has the original heads and valve covers. Everything else was sold with the car. Best offer will ship. Can provide numbers if need be. Thanks, Kyle