If you are interested in an easy path to decent power, Ma Mopar just announced 392 485 hp crate motors and install kit (computer, wiring,etc) for MSRP of about 11,500 for both motor and kit. I would guess you could get it cheaper by a couple of thou? There are a lot of advantages in going with a factory motor that was pulled off the regular engine line. Add in a good header and exhaust system, and it ought to be close to your goal. Ask around what the true cost is of a custom engine build and everything needed to match what you get with the crate motor, might be a cost effective way to go Plus the mileage , low speed torque and reliability will be excellent.