Had this problem since my rebuild with medium porting and retune.

Any time , any gear, at about 40-60% throttle at 4500 -5500 rpm massive hesitation. AFR's are in check at about 11.4 at this point and boost will be about 10psi. What could be the cause? At WOT no hesitation at all. Is i lean it a little it gets better, but I afraid to lean ir too much.

Anyone had this problem?

Mods

single turbo
medium street port
aftermarket ecu
1000/1600 staged inj

 

Check an adjust TPS, maybe.

 

what EMS? where are your secondaries set to start coming online?

 

secondary blades closed at that point? how about the timing?

 

he has posted about it in other sections, I think it is some kind of an injector staging issue