200 -250 hp ? What is so special about those numbers? Why not 500? If you want that kind of power, start with a 292, dollar per horse power will be less for the bigger engine and more torque will come with it for free.
Raise the compression, bigger camshaft, bigger carburetor, bigger intake, port the head for more air flow, headers and bigger exhaust pipe, loose the propane, and raise the drivable rpm range. One other option is a turbo charger, quick and easy horse power. Plan on spending a lot of money, 6 cylinders are not cheap to build!
Head over to ( inliners.org ) for more information, chat with Tom Lowe, he will get you where you want to go.
Joe
