Diagnosing a misfire

[Mrturner1]

Well I made some good progress. I decided to take the rocker arms and pushrods out to check everything because I started to suspect a cam lobe flattening causing the rockers to loosen up after I tightened them. Turns out the tips of a few pushrods were wearing down and this was causing the rocker to become loose. I got a new set of pushrods and reinstalled everything, and set lash at .017". When I took it out for a drive it misfired again, brought it home and set lash at .020" cold, and still a slight misfire. Tried again and set it to .020" hot and it runs fine now. I don't understand why the lash can't be fooled with on this cam, but I know it can't. Maybe some cams are different and have different take up ramps and lobe characteristics, and those can be set tight or loose?