440 6-pack crate engine – plugs not firing or valve issue?

My "crate" engine is a 1974 block, 1970 intake manifold and Edelbrock Performer RPM aluminum heads, with Hedman headers. I have had it about 10 days. It ran well at first, then one day I went to start it and it had gone from starting at the first turn of the starter to not starting at all. I had just bought the car 3 days before. I had driven it hard, but not too hard, a couple of times. I am talking about 3/4 throttle starts and such.

Anyway, when it would not start, I spent my first...

440 6-pack crate engine - plugs not firing or valve issue?
Author: wsr1961