tank vent?

Other than a few spins around the block last week, took my '74 Roadster for it's first real ride in 27 years. About 6 miles away, noticed that the exhaust was starting to snap and pop when backing off on the throttle. When I slowed down to return it stalled and would not start. Checked a few things but basically just let it cool down. Engine seemed hot. After 15 minutes, she started right up and got me home. Could the tank vent be not functioning and I ran out of fuel? Running AP 64 plugs and they seem too light. Could I be running too lean?
Anyone have any ideas?
Thanks
Mike

Well yea first check timming, Has to be right to do anything. When you are sure that it's perfect everything else is just common sense carbs, petcocks, quality of the gas you are using wireing and ,a load tested battery. I am still useing AP64's but you can change to Wrp7 Bosh plat. if you like I don't think that's the problem.

Thanks Norbsa. Done a static time but still seaching for my timing light.