New 15 STI
 

Hey guys, I just got myself a 2015 STI sport tech and I've been looking into making it ridiculously fast. From what I've read so far after a point I need to redo the engine and rotate the turbo to get above 400HP. I don't plan on this being an everyday car because I'm gone 3 weeks a month for work in Alberta so I'll only be driving it for a week a month. I'm curious what I should change out first and if I should redo everything at once or stage it. I've found a shop that specs in Subaru "Pacific Import Auto" in Tacoma. More than that I was wondering how reasonable the cost per horsepower is if you redo the engine with forged parts and rotate the turbo to fit a bigger one in. Anything you can say will be a great help.

NASIOC forums may be able to help you further. They are a dedicated Subaru enthusiast forum.

Thanks a lot!

+1 for NASIOC. Look for the VIC forum, and they (myself included) will be glad to give you advice, recommend shops, etc.

I'd start with things that will be relevant at all stages of a build. Exhaust to free up breathing room for turbo, more efficient intercooler (I chose efficient very carefully as a word because larger and more piping isn't always better).

These will last with the car in case you decide not to go with getting forged internals and bigger injectors and bigger turbo etc. Once you go into building the internals with forged pieces with bigger turbos, it's best to do it all at once with a standalone ecu, proper fuelling, and proper cooling, then dyno it all at once. The reality is the more safely and properly you do it, the more expensive it becomes.