What the W

I don't mean to give you the news but. Imperials and 300's only came with 440 4bbl's. I just looked at a 318 with that intake. It was in a very low mileage D500 Dodge truck. It had a weird carb and waterpump. The engine was a 318-3 which had a shot peened cast crank. very strong and bob weighted for heavier rods. You might have found a jewel. Very strong bottom end. The crank journals are not drilled they are solid.

Those cranks were use in big trucks to prevent breakage when letting the clutch fly in low range with 5 ton of weight on the back.