Turbo cooling

Some turbochargers are just oil cooled, others are oil and water cooled

Tor the oil cooling, you will need an oil feed and and oil return line. The oil feed line is under pressure and the return should be free draining. Use a -03 or -04 oil feed line and a -10AN oil return line. The turbocharger's oil return should point as close to straight at the ground as possible. You will most likely need an oil return flange, which converts the turbochargers square oil outlet, to a threaded 1/2NPT fitting from which you can run a -10AN male. The sump should be welded or tapped with a fitting, above the oil level to allow the free draining. A 1/2NPT to -10AN steel fitting works great. Be sure to clear the axle and downpipe. For the oil feed line you can run a 1/8NPT 'T' fitting off the oil temp or pressure port on the top of the oil filter housing or from the back of the cylinder head. Get an M10X1 to 1/8NPT adaptor, or just use a 1/8 NPT male, which is very close to the M10x1 threads that come from the factory. You can then install a 1/8 NPT to -04 (or -03 if you choose) fitting to connect your oil feed line. The other end of the 'T' can go to the factory oil temp or pressure sensor.

Engine Cooling

It is recommended to use some sort of oil cooler. The stock cooling of the 16v motor is and oil-to-water cooler integrated in the oil filter housing. You can use a oil cooler sandwich plate, either with or without integral thermostat, that sits below the oil filter housing, to allow you to fit an auxiliary oil-to-air oil cooler. You can either keep the stock oil-to-water cooler, and use the sandwich plate as well, or you can remove the stock cooler and run the sandwich plate and remote cooler on their own. This can lead to slightly unstable oil temps in traffic, but will maintain a lower oil temperature overall. The thermostatically controlled sandwich plate will give you quicker warming up, and a minimum temp (normally 80degC) when running.

Due to the very nature of forced induction and increased engine temperatures it is advisable to increase the size of the radiator, or at the very least ensure that a brand new one is used.