I'm new here and I'm hoping this is appropriate... I had a similar question about performance parts when I came across this interesting article entitled: Hyundai and Bisimoto ready 600-hp Elantra GT for SEMA
I thought this was very interesting and they list the names of the manufacturers of the performance parts that they used in this project. Imagine....600 HP in an Elantra!
It is a great build, but if you go to Bisi's website you'll see a lot, if not most, of the parts are custom made one off parts. That build would be insanely expensive for a regular customer. I would say most likely close to the $25k range. Now a small turbo kit would be nice for them to make though. Maybe say an extra 75hp or so that would be a nice setup.