Recently my 97 manual GT has been making this "whistling" noise when I accelerate / rev the engine at 2k RPM or higher; as if I have a supercharger installed... I bought the car used recently and it has approximately 34.5k miles. In terms of modifications, the car is mostly stock, but with an aftermarket exhaust setup and a Ford aluminum driveshaft (not sure if this changes anything).
Since getting the car, I changed out the transmission fluid, differential fluid, water pump, belt tensioner, serpentine belt, and idler pulley.
Would anyone be able to chime in on what might be causing this sound? I'm hoping it's not the transmission, but I'm not too sure..
Link to video:
Many thanks in advance!