What is the cheapest, fastest way to gain BIG HP?

[Isphius]

Yes, Mine is the same way. My n/a ran beautiful, Every time. Go outside in the winter and it starts up just like a brand new car. But my turbo runs like crap and now has a blown head gasket. lol. It wont start for crap. And once it does, It takes like 20 mins to warm up before it stops misfiring, And then when driving it seems to run fine, Like there is nothing wrong. But once it gets below like 1000 or 1100 rpms it runs like crap again and i have to nurse the rpms back up. Luckily its an auto, which makes it way harder.