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Old 10th Oct 2018, 12:50
  #84 (permalink)  
Bend alot
 
Join Date: Oct 2017
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Originally Posted by rutan around
Bendy,


My post wasn't about rich or lean mixtures. It was about incorrect timing for a particular fuel and how the head could get hot enough to cause valve recession. Without good data relating to where peak pressure occurred at various revs, what that pressure was and the actual CHTs at different revs it's drawing a long bow to blame lack of lead in LNG or propane for internal damage to heads. Taxi cab owners aren't noted for being silly with their money yet they continued to do gas conversions until gas became too expensive and hybrids became available.
Just state at what part of the cycle (rough degrees 0-360) that this comment of yours is possible.

"However if the timing is too far advanced ie the fire is lit too early all the fuel will be burnt at or even before top dead centre."
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