Inliners International Forums General Discussion Engines Engine Mods to achieve HP

Has anyone seen engine modifications organized to achieve certain HP and Torque levels. For example, a list of modifications (upgraded exhaust, ignition, headers, etc.) and the general HP and Torque improvements that could be expected. I want to get about 250-275 HP from my in-line 250. What kind of mods are most cost effective to make to achieve that?