70 MPH corrected airspeed, 5900 RPM, 170° water temperature and 950° EGT on both cylinders.  The water temperature was telling me something but I rationalized that the outside air temperature was cause.  The EGTs indicated I was runnning slightly rich.  Normal EGTs are 1050 but I knew I was throttled higher than normal to make up for the headwind.  It would take its toll on the engine soon enough.