So now the chain is too long, but it has no affect on performance. The spec  is for droop when the chain is off the engine and held side ways to check for  wear in the link joints. Still doesn't matter. Even warn out they work just  fine. Up to 115 pounds of oil pressure. There is a tiny hole in the pump that  sprays lube oil into the pulley to lube the chain. Have never seen one break  since 1980.
 
Lynn E. Hanover