Have PFS purple computer + other basic upgrades. Just noticed, on highway, downshifting from 5th to 4th, accelerating hard, car will not go past 5200RPM in 4th as if something, somewhere is putting some type of limit. When 5200RPM is hit, I can hear extremely loud exhaust sound as if it's been clogged.
Recently installed N-Tech high flow catalytic converter which increased the power noticeably, it also increased the boost climb up from 15, PFS set on high, to about 15.5. No reprogramming of the computer was done.

Any ideas?

 

When it happens, switch your ignition off then back on (yes, even while driving. I keep the car in gear when I do this to keep the oil & water pumps turning, though it's only for a second.) This resets the PMS computer. It's a glitch that only affects certain FDs.

 

I'll try that, Thanks!