Wing incidence, balance and thrust all play a factor in this. Start by double checking your CG (You do NOT want to get a Kougar tail heavy!) and then check your wing incidence. Make sure you don't have a ridiculous amount of positive. Lastly if you've checked everything else, do a thrust line check.

A Kougar needs a good bit of down elevator inverted, but not an excessive amount. It doesn't like to slow down though.

Have fun,
-Mike