Tim Cnrad's T-28 very slow...please help!!!

Hello guysSomeone could please help me to understand why the gorgeaous Tim Conrad's T-28 trojan is so sluggish??It is hard to get the bird to reach 70 KIAS down the runway and if I'm lucky I can get 1000 f/min climb rate at full power.Accordingly with the panel's gauges, I reach the full power indications (RPM and Manifold pressure) of the aircraft.cfg parameters.It seems weird that a 1425 HP and 350 mph+ plane behaves worse than a C-172 at take off.Thank you very much in advance for your help!Regards