I ordered a set of Xona Greens today and will report back my findings. I am going to install my downpipes in January and then dyno to get a baseline. I will then do a before and after showing FBO vs FBO w/Xona Greens on 93 octane.
People to ask should be Extreme turbo systems as they are the only ones really pushing them on their kits,xona are very well built turbos from what i could see and know of good results on them with porsche 996/997 turbos!
In for updates too! I think the Greens are too small for me, I'd probably do a Red. The good thing about the Green is you probably wouldn't have to replace 2-6 gears so a drag 800 would be perfect and significantly cheaper. The 800whp mark seems reasonable to achieve, but things get ridiculous if you go for 1000whp since you need to spend an extra 10k for Drag 950 or Shep 1k. I just can't decide what to do.