If I changed out the heads on my 1998 gt with ones from the 99-04 gt's and planned on upgrading my throttle body and air intake as well, would I buy them for the 96-98 or 99-04?

 

You need the pi intake to work with the heads then parts for 99-04

 

So I would have to do more to the 98 4.6 to make it a newer version with more power? Sorry I just got my 98 and I'm just trying to get the most power out of it I can..

 

With the heads from a 99-04 you will need the intake manifold for that as well. I would use an aftermarket throttle body with it for a little more power but i think you can use the stock throttle body from yours on the swap. Best thing to do is go to american muscle or another site and look at throttle bodies. See if they list for 96-04 or if its listed as 96-98 and 99-04

 

some say 96-04 and others say 96-96 and 99-04. thank you for your help

 

I have a 65mm tb if you want it. The real restriction in the 99-04 air intake is the plenum.

 

I might want it.. I'm not sure if i have one hanging around. I was plaing on buying a bbk intake and manifold with the new heads. Ive never replaced heads on this kind of car so I'm not sure what I would have to do to it. I have a 1990 5.0 but I ended up crashing it but the motor and tranny is fine so I have not had much practice repairing or modding the engine to much.