Unless you are gonna do some serious racing, why tear the motor apart .If this motor runs as well as you say and all you have to do is minor stuff, then leave it alone and drive it. More HP means more gas, more heat ,so you may have to upgrade the radiator and finally more HP means more headaches.
I did the race car for the street thing. It is fun but its also a pain in the ***. Have fun with the car and just drive it.