ZX2 Power

I own a 1998 ZX2 and from whaty I've herd the car puts ouit about 135hp but thanks to it's light weight it still feels peppy, i was hoping to get the car up to about 160 or 170hp without spending a pile of money the car has enough power low down for my daily driving so I'm looking mostly for an increase in the top end of the rev range, what would be the best way to get an extra 25 to 35hp I also have some experince working on cars myself (changed steering racks drive axles brakes) so it would be much appricated if you could list the modifications and how easy they are to install, Thanks for your time

www.TeamZx2.com

That should answer your question.