Many performance enthusiast dismiss the importance of an oil catch can thinking that since it does little for carbon build up it is of little use. Nothing could be further from the truth. In turbocharged applications the octane of the fuel in the intake charge is critical. Lower octane fuel simply cannot resist detonation under high boost or aggressive timing, both of which are needed to make maximum power. Without an oil catch can, vapors containing oil mist enter the intake track just forward of the turbocharger and are carried into the engine. This can have catastrophic consequences. If you are running 93 octane fuel and oil mixes with the intake charge it can lower the effective octane to 89 or lower. Many people wonder why even a stock, well maintained turbocharged vehicle running Tier 1 fuel can suffer a piston failure. An effective octane of 89 is your answer.
We highly recommend the installation of a quality oil catch can unit for your turbocharged vehicle. This is not an area you want to skimp on. Invest in a quality unit, preferably with internal baffling, and having large inlet and outlet ports of 5/8 to 3/4 of an inch in diameter. Most of the inexpensive units on the market contain zero baffling and have ports as small as 3/8 of an inch. Units of this size will have a difficult time catching anything and struggle to keep up with the flow necessary in high boost applications.