need advise in a 318

Mopar may have used the same casting number for the early race block. If I remember right they were stamped as being a 318. Maybe that's where the confusion came in. The chances of it actually being a race block installed into a camper van is about as good as finding the proverbial needle in the haystack. That doesn't mean it isn't a good engine by any mean. The 318 is one of the best engines ever produced by any company IMO.