You are asking a lot of things that can be variable. The head os the IXA is a little different and may be a lower compression to start with. The key thing is your wet readings are fairly even, 10% variation being the usual allowable limit. Did you take all the plugs out when you did the check how good is your cranking speed and so forth. I would put a few hours on it and check it again. Also then change the oil and filter to get rid of the &amp;quot;sludge you have worked loose in the engine.