Only way to accurately measure compression ratio of an engine is to cc the combustion chambers.
 
A dry compression test will tell you if your rings / pistons, head gasket and head are OK and a general idea if your engine has high, low or OK compression only.
A wet compression test (where you squirt a little oil in the cyl) will tell you if it is the rings that were bad (if the test is significantly higher that the dry comp test)
 
If you have a bigger cam than normal then be careful of advancing it one tooth as it may then "catch" the piston if it was correct.  If is is a standard cam then it does not matter as the valves do not meet the pistons even if a belt breaks at higher revs as there is some space between the valves and pistons.
 
If it is all low end torque an gutless up top with good compression, a "normal" (not huge) cam, properly gapped plugs, dwell set up correctly, valve clearances set to tolerance, properly set ignition timing and no vacum leaks - THEN try advancing the cam timing as all the rest need to be right FIRST...
 
It is not very common, but one of my engines misfired (once) when starting and retarded the cam by a tooth once in the last 20 years and in over 250,000km of pinto driving - so not a common occurence.  Most causes are more normal run of the mill.  If it is a fresh engine, then definately check EVERY thing else first....