i have read in a topic somewhere that a guy tried to mod his b20a5.. got crower regrind cams, adjustable cam gears, header, greddy exhaust system, and custom intake and got nowhere but maybe 20 hp and spent close to 2 grand. not worth it really. make sure the engine is healthy on bottom as well as top and peice together a small turbo and run around 8-9 psi of boost...for 2 grand you will get more than 20 hp going with a good small turbo setup.