Yep, definitely a different objective. The "rolling coal" crowd is only in it for the entertainment value.It may not be the same but my Dad had an Allis Chalmers dealership (1957 - 1977). They put the diesel tractors on a dyno to tune (pre electronic). His top mechanic always said if it's blowing lots of black smoke you're just wasting fuel. They got top torque with just a wisp of smoke at high rpms.