T2 FC3S

I have a 88 turbo2 with 25.000 on a streetport rebuilt engine from RP. I was driving the car yesterday in the freeway when a BMW pulled up to me, I down shifted to third and took it through fourth. In fourth gear I wasnt even punching it anymore I was pretty much cruising. I put it in fifth and was going about 75 and about a quarter mile down the engine just started bogging. I automaticlly felt the power loss. The car never threw smoke or died on me it just feels really weak and started making that sputtering sound. Im about 90% sure that one of my rotors went out. I sounds different and has all the symptoms. I dont know why the hell it would blow up, I took so much care of this car and it just slapped me in the face. The car still runs and moves but just barely. Is there any thing I could do to make sure its a for sure thing???I want to be absolutely positive. Im still hoping its something else since its my daily driver.


Mods:
1988 turbo2 Rebuilt engine with a streetport and 3mm apex seals at 117 now at 142(rotary power) Haltech E8 with manual boost controller set at 10psi "safe tune" by speedtech,supra tt fuel pump,RC injectors 890cc,LS1 coils, NGK plugs, boch wires, full exhaust,clutch,flywheel, Intake, removed smog pump, blockoff plates,etc............

90WhiteVrt

I'd check all your vac lines and IC hoses.