dude, my math is fine if you are going to quibble over 10$ you are just being dumb, and as far as the hp goes if you go on ebay those prices check out let's do some math: cold air intake lets say10-15hp, chip 10-15hp, headers 5-10hp and those are all conservative and if you want a crazy money exhast you can get that for like 400$which can give you 15hp so for well under 1000$ you can totally get your type-s to at least match the wrx, and still have a more stylish car.
not to dis you pwman, i see your point but all those prices do check out look for yourself.
i should know because i've done it to mine and i've walked wrx's with it......