Using 1290-1310 is fine.  What I don't understand is why the EGT is climbing
as you climb. 

Walter,

 

If one assumes no ram air, one would expect the EGT to drop as the mixture becomes richer with the altitude gain.  I think, in my case, initially as speed increases after takeoff the induction ram air actually leans the mixture for a while until the altitude gain overcomes the ram effect and the EGT starts dropping below the target value. Rotation starts at 70 KIAS and climb occurs at 135-140 KIAS. 

 

I get the same effect (assume leaning in the climb to the fixed target EGT) when I level out and speed increases to 175-180 KIAS (Still WOT, 2600 RPM until cruise speed attained) - that is, EGTs increase and I enrichen the mixture at bit to best power with a resulting reduction in EGTs. 

 

I don't know exactly how the 4 air tubes in the throttle body throat precisely affect the fuel delivery at WOT other than they are measuring the induction air and adjust the fuel flow.  Note also that my injector atomization air is supplied by a separate ram air "pitot."