well ima change ma top mount to a front mount on my 04 sti, but idk whihc one to buy, hows greddy?.....or aps, but also keep in mind im not rich.....lol....but yea l need help and hopefully this wo not void my warranty ofr ma car

Call a subaru dealer about the warrenty.

As for which intercooler to get, ask on NASIOC.com. they know EVERYTHING about imprezas. Thats the best place youll find the answer.

This should not void a warranty, as long as you are not upping your boost as well, there are many other upgrades you can do before you heat soak your topmount. l have a Greddy on my S13 and it good for the price, the only down side is the poor quality couplings, l replaced with 4-ply Vibrant.