I have a f22a made 460whp at 23psi. when i dynoed i made power from 5k to 8k when the boost is @ 8 psi to 15psi. once i go over 15 psi or 350hp my car will not pull to 8k. it just get rich and you have to take out alot of fuel. i am thinking its the intake manifold. things i have tried different tuners lol, spark plug gaps, heat ranges and brands, racing fuels, down pipe sizes, turbos, and cam retard.
here is a list of parts i have on my car.

bisimoto pro springs
bisi 1.2 turbo cam.
h22 h beam rods
wiseco pistons
ram horn manifold
hx35 hx40 61mm turbo
3" down pipe and open exhaust
stock intake (butter flies removed)
stock tb
1000cc fic

 

you can see it here this is a 17psi and 19psi pull. if i would have done a 12 psi pull the hp would have climbed to 8k

 

It looks like your hitting a wall pretty hard. Despite boosting more its clearly not flowing more. Hows your air filter. Have you ever tried making a pass without it?

 

Might want to change your fuel filter, I've seen that happen before when the filter is partially clogged.

 

those are with out air filter. i dont see how it could be the fuel filter because it not starving for fuel.
i am hoping its the stock intake and throttle body. the f22 has a pretty restrictive intake.
its in a EG i went 7.0 @103 in the 1/8th.

 

have a nice day

 

its a sohc i cant retard the intake

 

HA. Time to try a new cam then.

 

the cam is mild its like a 268/262 duration. i think i am going to try a delta regrind. delta 282 duration they are 96$ to regrind. i have seen some good results in a dsm from delta. if that dont pull like i want then i will save up for a bisimoto 2.4 cam.