Same here, I have not been able to pull more than 220 kts at level flight at cruise clean configuration, even with cowls, oil and inner cooler flaps closed. RPM and Man at max, all flaps closed wont get pass 250 kts, at cruise, 2550 RPM and 48, a little over 210.... I tried different mixture and blower settings but nothing improve the power... It seems very slow when compared with the mustang or jug, which at cruise at sea level go above 300 kts