We no longer recommend using oil supply from the cylinder head for the FP Journal Bearing turbochargers for the Mitsubishi Evolution 9. Oil pressure measurements made on various engines indicate that in many cases the amount of available oil pressure at the cylinder head feed location is less than adequate. The factory head feed location prioritizes the turbo oil supply lowest, after all, other oil supply duties within the engine. These turbochargers require a minimum of 45psi of oil pressure under full engine load, and sourcing oil supply from the cylinder head simply does not meet this requirement.

The filter housing source is much higher pressure than what is available at the cylinder head. Relocating the oil supply to the oil filter housing allows the turbocharger to be fed a sufficient supply of oil pressure and volume.

Some people may insist that 20 or 30psi of oil pressure is sufficient to supply a typical floating journal bearing turbo, it is our specific experience that this is not true in the case of an automotive racing turbocharger used in a performance application where excessive EGT, high shaft speed, and maximum thrust load are the norm, not the exception.