the whinning could possibly be your trans gears making noise, exactly what causes it, why, or if thats really it i couldnt say. But have heard of whinning coming from the GSR trans b4.
Your best bet is to tell us what you have, like if it is a bone stock gsr, say that, cuz then we know what injectors you have so on. Its really hard for us to guess how your car is feeling you need to explain to us, what is making it feel slow. So try and give some better details. You can always try a retune, and obviously you got the motor used, so was it from a place with a start up promise? Maybe you have blown rings.