> Makes me wonder if you're hitting the 4000 rpm rev limiter built into the 
> injection pump?  Doug
> 
  Isn't the max rpm ~5400 for a 1.6 NA, ~5600 for a 1.5 and ~5100 for a TD?
Not positive but it seems like the Dodge Cummins (NOT a high speed 
diesel) redlines at almost 4000.
     Loren