The proper cam will make a world of difference. Valve events and overlap are 2 big parts of a good turbo cam. Ive found quite a bit of good info regarding this over on yellowbullet, john bewley of lil johns motorsports would be the guy to talk to if you just want to have someone spec a cam for you.
Also a good set of heads and proper converter, the 318 can be done just depends on intended use and budget. Look at the amount of 5.3 ls combos running that turbo. I know there are other factors at play there but cubes are cubes.
