Engine numbers back in the early 1960's were not that long. For 1961, the engine number on an Imperial would have had prefix "R 41" or "R 413", followed by digits for the date of assembly. A third digit, "2", after the date meant the car was built on the 2nd shift that dat. The car's serial number was not stamped on the block and there is no way to prove the engine in the car was the engine the car was built with originally. Bill Vancouver, BC > Hello Imperialists, > > I am considering a 1961 Imperial that is not in my home town and am trying > to determine if the engine is likely original to the chassis. The owner > found the engine ID boss that's located around the base of the distributor > toward the driver's side, but the ID number he finds does not relate to what > Year One says about identifying big block Mopar V8s. He says there is only a > four digit number stamped on the engine boss. > > It would be most helpful if someone with a 61 could give me an idea of what > the ID is like on their car. > > Much thanks, > > Bruce in Tulsa > > >