Originally Posted by Seraphim38

5.0 motors are big and difficult to fit but can be done and can make big power if built.

For the rear end, the axles are the weak part. Get either DSS level 5 ($1,000) or Mazworx axles ($1,800), which support 500+ rwhp. Neither are cheap, obviously. Rear ends in 240sx are stout, though a KAAZ 1.5 or Nismo LSD is suggested.

Fuel system; depending on your power goals, dual Walbro 255lph pumps, a single Aeromotive 340lph are both solid, low maintenance options. Dual Bosch 044 pumps would be overkill and you would need a quality Aeromotive filer post-pump to remove any materials that come from the brushes in the pump. Aeromotive A1000 is overkill, requires a controller to be done right, is noisy and etc...

Since my last car was a built, supercharged mustang cobra, I can vouch for the fact that they can make strong power.