Yeah, Dave, its going to be tricky to fix. I've got a spare 48 hood that has the same basic edge shape; i'm thinking of using a patch from it. Not sure if I want to cut it up or not in case I'd need it in the future.
Gary, I thought the same about unleaded gas when I put my last flathead together but there's some good research out there that shows it's not too big of a deal. Here's an article put out by Chevron Corp that did some research on it:
Unleaded Gasoline in Cars Designed for Leaded Gasoline
With all the media attention being given to the reduction of lead in gasoline and the potential of phasing out leaded gasoline, many consumers are asking the question "If my car was designed to run on leaded gasoline, will it operate satisfactorily on unleaded gasoline?"
The answer to the question is yes. The chief concern has been for the possibility of exhaust valve recession (sink or seat wear) when these engines are operated on unleaded gasoline. After 15 years of experience in marketing Chevron Unleaded Gasoline, we felt that enough accumulated data could be obtained from different sources to allow us to finally arrive at some definite answers.
Passenger Cars and Light-Duty Trucks:
Based on an extensive survey of the published literature, fleet operators, engine rebuilders, and manufacturers, we conclude that all typical passenger car and light-duty truck engines (representing 94% of U.S. gasoline consumption) are safe from valve recession when operated on unleaded gasoline. They are either equipped with induction hardened valve seats or subjected to service too mild to cause problems. The problem can only occur in older engines when operating under sustained high speeds and loads.
Vintage Vehicles:
Antique cars are typically exposed to such light service that they are not expected to have any valve seat problems. In fact, they stand to benefit overall from a reduction in exhaust system corrosion and oil contamination.
