Put the piston at tdc with both valves closed.
when you hook the gauge up to the compressor, you zero it then after that.. hook to the cylinder and see what percentage of leak you have.
you mention 20...I assume you mean 20% leak down, not good.
at the same time...g force smoking=leaky pan onto header/exhaust maybe.
tan plugs?
what part is tan?
you could be running too rich like that and not know it, black would be an eventual catastrophy.
you haven't had any exhaust leaks on the no.6 with those headers have you?
enough of a leak and burnt valve city...
btw...the only way you would end up with the ring gaps staying lined up is from an out of round cylinder, like 2+ thou or so.
