If you want to keep the engine in good condition, abandon your intent to get more power from it. The engine was designed to produce a certain amount of power. The more you ask of it, the harder it runs, the less likely it is going to be to last long.Sure, you can upgrade all the parts, and attempt to postpone the damage, but if it was meant to be a higher horsepower engine, it would have been built that way in the first place.Also, stop driving it at high rpms. All that's doing is increasing speed and heat inside your engine, which is no good for it. Particularly, if it's not serving a purpose. Drive normal, switch over to some synthetic oils, have the gaskets/seals switched out on schedule, etc, and the engine should last you a long time.