trying to determine exactly what i have....
 

what do you mean when referring to s4 or s5????? i have a 89 gtu what do i have in those terms and what is the best way to go about modifying what i already have??? i already have a centerforce clutch in...tune up,, fresh filters and oil and a racing beat dual polished stainless exaust...where should i go from here??....oh yeahi also have eibach springs and koni shocks

You have a S5

S4- 86-88
S5- 89-91

Sounds like your car is in pretty good form. To learn more about your car, read, read, read on this forum. Especially look at the FAQ. Lots of good info there.

That truly is the best way..read up on anything to learn more.. researxh!

thanks to those of you who replied....i love this car and will be doing alot of work to it....the wife to be already calls it the mistress...

i am in deed still looking into more.....i have desires to make around 300 hp but am not sure what direction i should turn to on it.......i see that na engines are not good for turbocharging....will t2 rotors fit inside of my rotor housing????i want to turbo it but not exxessively overdone...and i want dependability.. i know i will be spending some cash...other than forced induction i am not sure where to get more power from now....any ideas would be helpful..thank you in advance