Cheaper?? You have it backwards.
On an import like an RSX, everything is more expensive and everything breaks and needs to be upgraded. Engine, trans, diff, axles, chassis, PCM, you name it has to be modified or replaced. Do you have any clue how much it costs to build a Honda K-series to make 600-700WHP?? Apparently not my friend, because its astronomical.
All of my buddies and all the local guys have less in their motor builds than I do in mine; expensive sure but less expensive than building a v8 was my point.