I think my 1973 Chevy C20 454 needs a new camshaft and I can't decide which one to buy. I drive my truck maybe twice a week with an occasional trip to the dump. The 454 is stock and I'd like a little bit more power but I don't want to make the mistake of buying a "thumper cam" when I just need one a little above stock specs! Can someone explain "lift & duration" to me in laymen's terms?
