Ringed engines
Av8tor,
Ringed engines need a richer, more prolonged break-in procedure, compared with ABC engines. I had to see the MAN shootout to realize you are not comparing the same engines. Before I just heard about it from friends and from the forum.
BTW, the Fox and the Tower are the winning candidates.
Most small displacement model engines, which produce high levels of power, are ABC engines (C for Chromium, not Composite). Larger displacements don't even exist in ABC, unless there is a ring included in the name (and in the engine) like some Super Tigres and others.
I suppose the Fox ringed version may produce slightly less power, than the ABC version tested by MAN.
Sincerely,