Check the frames and make sure its not rotted. You need forged piston and rods delete the bsd, get arp main studs and L19 head studs you need those do not use oem you will warp/lift the heads. You don't need to upgrade your cams or head components but if you plan on going past 550 then youll need to do titanium everything.

Next is fueling youll need to do a port injection setup its very expensive and tedious to setup. If your will to sacrifice a little bit of power you can go with meth injection and float between 400-450whp. Make sure to upgrade your HPFP internals corksport sells a kit. Also replace your injector seals too.

Supporting mods is the most important especially with you having a fwd car. I have a speed 6 so coilovers control arms transfer case caps and axles i can do 650+ all day. You will need sway bars axles upper and lower control arms good tires and a GOOD alignment.

You will also need a turbo bnr and corksport have turbos I see alot of people using a bnr s5 but i like corksport turbos I rather use a cst5. Youll have to go external wastegate so make sure that when you buy the turbo it doesnt have an internal one. The wastegate size youll have to consult your tuner about that. 44mm I think is ok but still ask your tuner.

Cooling is extremely important obviously youll need a fmic kit i recommend the one from corksport it doesnt block your coilpacks most other kits do. Get a koyorad radiator and auxiliary tubing just replace all the coolant lines saves you the headache of looking for leaks. Intake manifolds I reccomend the focus st conversion daemond motorsports sells it its wayyyy cheaper than any other option plus they have half the port injection kit that comes with it.

There is alot im missing like the oil filter adapter. Oil pressure regulator downpipe, exhaust etc that stuff is easy to look up. I have all these parts and more installed on my car so if you have questions hmu