Yep . I cut new cores , with more span,less sweep and wider tip.... Im still not sure what to do yet.. Im sorry ,but i found the,little "magic" we use on the wings do help.. Fences,vortex generators, L/E RADIUS for sure. Crow also on many aircraft.. T-45 is a DEMON ,without these design patches.. what planform wings do you fly?? Thanks for info and time