I am sure it doesnt have OPTIMUM airflow/performance.I think that would be a secondary issue,still worth addressing.
Focus on the timing issue, that is probably the biggest part of the problem. Knowing the other engine puked I wanted to voice my concern that the exhaust could be plugged. Just one other possisility that could be left over.
I have seen plugged exhausts destroy an engine from the heat from a fuel imbalance in the system that creates a blast furnace in the cats and melts the engine and the cats down into scrap.Just my years of experience talking. Take it or leave it.