Hello all.
I have a 1992 gtst with a rb25det swap and a power fc
The car will rev really good until 5k then kinda just stops and sounds like 2step splitters and doesn't really want to go past.

Changed spark plugs
Liquid taped the coils
Cleaned maf
Haven't had time to check for boost leaks but pulls great vac and hits full boost on the gauge when driving but doesn't feel like it goes anywhere feels slower than my focus st.

whats your engine setup pal, has it come upon sudden or there from the star sounds like you probz hitting a leak somewhere down the line.

Found the cause was a loose turbo pipe that goes to fmic only went loose on strong boost. Repaired and cures. Many thanks