Most of your HP gains on a N/A are going to come from lightweight parts. Flywheel, driveline, wheels. It doesn't actually "add" horsepower to the engine, but it does get more of the HP to the tires. Flywheel weighs about 15 lbs I believe, you can get 11 lb ones. Driveline I think will lose you another 5 lbs. Stock wheels weigh in at 23 lbs, so depending on wheels, you can lose alot of weight there too... The ones I'm looking at are 17 lbs, so 6 lbs per rear tire. Front tire weight loss is negligible for a horsepower gain, but can gain you cornering performance and braking performance.

....uhhh wtf are you talking about? i have an N/A with a 3" downpipe...

downpipe
 

are you talking about headers?

because a downpipe is the exhaust that comes off the turbo elbow or can bolt right up to the turbo.

headers come right off the manifold of the n/a.

Man I really have to work on my english better. Sorry my fault I was confused about the names. I stand corrected. LOL at least now I can change my sig to correct.

Ok then what is the section of pipe called that goes from your headers to like the middle of the car?

exhaust
 

this would be your catalytic converter then your exhaust pipe?

i don't know what else it could be.

hmm, well I was all excited lol.

did you mean header

Yes, A header replaces the stock exhaust manifold, And connects to the cat. you will probably see a nice high end increase with a header/cat/full exhaust. As for the lightweight stuff, yes this will also help a lot. the key to making power out of an NA is getting the air in and out faster and more compression, whereas with a turbo its getting enough fuel and boost.

ive recently added a 3" exhaust elbow (bought from supra_girl) direct from turbo to custom 3" exhaust - made a BIG BIG difference, espeically in the low end.

The factory elbow is probably only 1.5 - 2" in diameter, very restrictive!
With the full 3" elbow the turbo spools up much quicker after shifts, i would def recommend to anyone with 7MGTE if youve got full 3" exhaust.

Air filter is a standard pod filter, which has worked well, you can hear the turbo working now!
It sounds mean in cold conditions and goes much harder, again would def recommend.
I have just installed heat sheild around the filter, as it was sucking in all hot air from engine until now, which wasnt helping...
Next will be piping from front of filter to inside of bumper to get purely cold air goin through.