My guess is it is running way lean as I just about asphixiated my family a few weeks back even with the garage door open and two fans going full blast to ventilate things
. We had to vacate the house and spend the night on the boat! I wanted to get the cooling situated before getting it on a dyno and having the carb set up. I may just throw in some richer jets as it seems to be starved for fuel.
Thanks for the suggestion as my next step is to pull the heads to verify the gasket orientation.