Hey guys I have recently got a 440 out of a motor home and I thought that all of the motors in them had a casting number if 440-3 but this one has a 440-1 as if it came out of a car any insight will be greatly appreaced thanks in advane

 

As to what I know the 440 -1 means one part of the sand casting was replaced when it was made. 440-3 means 3 parts of the casting have been replaced