Having issues.
 

Hello everyone I have a 93 250 cummins with a set of 5x14 injectors, denny 2 fuel pin. Hot screw and a dynamic timing spacer. Cpp pusher intake/ 58mm hx40 and a 95gph fast lift pump. I'm having stumbling issue's under a slight load about half throttle. Starting around 15psi boost and it clear's up after 22 to 23 psi. If I just get right after it I don't have any issues. It might stumble a little in that psi range but it's not nearly as bad as half throttle. It's just a haze of smoke when it does this. Is this a possible boost or drive pressure leak?