Hi im new here and i need some help or comments. i have 97 Z24 with intake, headers and cat back exhaust.
i want to get more horsepower and torque.

and i would like to know what give me more or what is better for the car. changing the throttle body (TB)? or changing the pulley?
i know what each do but i dont know which one give more or is better.

This next questions are if i choose one of the the two.
if i choose to change the TB do i can still fit the intake that i have in the new tb? or if i want to change the intake mani and TB do the intake will still fit or i have to get a new intake.a diferent one??

if i change the pulley, is only one pulley or i can change all the pulleys? (sorry i dont know very much about it)

Thank very much all comments are welcome.

Best gains, simply, the throttle body. The crank pulley will also give sweet gains, make you rev a bit quicker, and gives better throttle response, but as far as raw HP, the throttle body is what you're looking for. You should NOT have to get a new intake. I used the same intake on my stock throttle body as well as my enormous throttle body and the fitment was perfect for each. The "larger" part of the throttle body is the inside diameter, not the outside diameter.

You can change both the crank pulley and the alternator pulleys. Some company out there has an A/C bypass pulley, but then of course you have no A/C. The combination of the Unorthodox Underdrive crank pulley and the AEM Underdrive alternator pulley will use the original belt, or at least an original sized belt, so you should not have to hunt for a new belt of a different size to get this combo to work.

Overall both are great choices. The TB is not hard at all to install by the way. Just pull all that crap off the original TB, and put it right back in the same place on the new TB. It took me maybe 15 minutes to do, and that's just beacause I had to adjust the idle afterward. Crank pulley is a b**ch and a half to install. There's some awesome step-by-step writeups floating around out there on how to do it.

Team Forward Motion Go there to see install instructions for both the throttle body and underdrive crank pulley.