Back in the 50-70's the additive was called "dry gas". It was used to prevent gas line freeze up in the winter. I would experience carburetor ice up if the outside temperature was below 55 degrees in my 67 Ford pickup. That was when the gas tank was behind the seat. White ice buttons would form on the secondary venturi's as I was driving down the road, especially the expressways. One can of dry gas per fill up prevented it from happening. I do a lot of small engine repairs for my friends and neighbors. Nine out of 10 times it's a junked up carburetor.
Rick
