Closed deck is not necessary for this power. A semi closed deck is what I would recommend. Though if you're going to do that you may as well go closed deck. Who knows you may want more powerrrrr later on?Im thinking about buying a new 2017 STI. Id really like it to make more power but would not want to have to worry about something going wrong since the warranty will obviously be compromised. So if i wanted 400 wheel horsepower or more whats the best safest route and how much would it cost? I know all the basic parts evolved when tuning these cars for more power. But i want reliable power. So aside from all the bolt ons like down pipe, upgraded fuel pump, exhaust, injectors, blah blah blah ect ect... For reliable would it be necessary for forged pistons and a closed deck block? Or would the pistons be good enough? And what would the typical cost be for 400hp? I know for 300hp to the wheels stage 2 its about $2900..
