I was looking at going the k04 route but now that you've suggested a gt25.. it sounds a bit more promising.

Are the other necessities the same as well? FMIC, larger injectors (440s?), tuning (GIAC?), fpr, and exhaust/clutch? Or will more be needed for the GT25.

 

Yes you pretty much have to do the same supporting mods when going to a larger turbo. Best thing to do is to find a kit that includes everything, some times you can even get the supporting mods along with the kit as a package and save money on all the parts. Turbo Kraut just posted a thread not long ago about buying and installing a Elim kit on his B5 A4 1.8t.

 

as mike stated i did just purchase the gtrs kit from him... great guy, helpful, great knowledge, great parts

https://www.audiforums.com/forum/sho...d.php?t=147327