best engine?

i have an '03 lancer oz and am looking to push the hp to around 400. my question is whether i could get to these numbers with the original 4g94 motor (swapping the internals and running an HKS turbo) or would i need to put a different engine. if a different engine, is there an alternative to the expensive to install 4g63 (such as the 4g93).

i need a factory front bumper cover for a 2003 lancer LS. If there are any conversion fanatics on this thread that have one laying around let me know

It costs a lot to swap an engine, but the best plug n play engines for your money will be the 6a12 or the 6a13 engine... which are only found in australia i thin... so good luck...hehe