ORIGINAL: skeeter_ca
Hmm.... the plane definately is faster and i can't think of any other reason than that.
skeeter
Recheck CG location; advanced location imposes higher load to the wings.
Check prop ground clearance (allow ~2"), for max diameter; then adjust pitch accordingly.
You could use this chart as a guide:
http://www.top-flite.com/accys/topq5000a.html
Isn't your plane a PT-40?