car bogs down at 40 mph an will kill 250 6 cyclinder
Gas filter? float in the carb? It appears to be a fuel problem. Replace the filters in the gas line (if you have one) and check if they are full or have junk in it. Then check if the carburetor float is working. It will float to the top of the bowl if working. Some old carburetors had foam floats and they got saturated. Others have thin metal that get pin holes in them and don't work. Or take it to a garage and have them do it. Expect to pay for a new carb and spend around $300 if a garage does it.
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