Good Afternoon Everyone:
Removed the cylinder head and all appears fine. No bent valves,piston looked intact, no antifreeze in oil. Prior to the rebuild there was antifreeze in the oil, hence the rebuild. All looks fine, I'm puzzled about this. I'm about to put the carbureted head and see if it does the same. In the mean time, to answer some of your questions, this is a B20 with the cam on the side. All rocker arms, push rods appear fine as well. I removed the valve cover while engine was running as someone had suggested and they all move up and down, however, I don't know to what degree. They all seem to be moving up and down the same across all valves.

I'm going to try and put the carbureted cylinder head this weekend and come back and let you know what happens. I'm on my third headgasket with this build. Will be re-using the last one as it appears to be ok.

Thank you all for your input.

Luis