ok i tore apart my s4 turbo motor. the back rotor and housing is destroyed. meaning. major scores in housing and scores in the rotor. where the apex seal sits on rotor, they are in good shape. but the rotor has so bad scratches. can u use either. could i use na rotor housing.

i need a s4 na engine or turbo engine.

 

sounds like you simply need to pick up a used turbo rotor and rotorhousing, no big deal, such damage is commonplace with blown apex seals.

You could use the NA rotorhousing, if you swap the exhaust sleeve out with the one from your dead turbo housing...this takes some doing, though. You'd need to run the NA housing in the front of the engine, and move the turbo housing to the rear...due to the coolant port on the turbo's LIM needing to be fed by the coolant port on the turbo rotorhousing, which the NA lacks.

The NA rotor is a different compression ratio, do not use it.