I'm waiting to see the answers on this one. I just can't imagine not having exhaust gaskets of some type. Wouldn't you get alot of blowby?? One time with my blown '57, I thought I heard a valve ticking. Was almost positive that was the noise. Took off the valve cover, made the adjustment and nothing happened. Come to find out, it was a header gasket that was partially blown. Can't even imagine the noise the engine might make, Carmine.