We think any turbocharged application should run a blow-off valve, but there are only two reasons why you should upgrade from the factory unit. The first reason is the customer wants the noise of it venting to atmosphere, and the other is the factory BOV leaks under higher-than-factory boost applications — some do and some don’t. If you aren’t running much more boost than factory, there is no real advantage in changing it. In our opinion, a vent-to-atmosphere BOV shouldn’t be used with a vehicle that has a factory computer and airflow meter. When the BOV vents, it is dumping a whole lot of air which has gone through the airflow meter, which as far as the computer is concerned is the air that has gone into the engine. For example, when you pull up to a set of traffic lights and button off the throttle, the BOV will open, dumping the air out, but the fuel will still be injected into the motor, which can often cause stalling issues before you come to a halt. Some vent-to-atmosphere BOVs run better than others with a factory ECU and air flow meter, such as the genuine HKS SSQV when compared with the common TiAL and Turbosmart units. To be honest, people normally have one for the sound over anything else. If you run an engine with an aftermarket ECU and no airflow meter, then you’re pretty much free to run whatever BOV you want, plumbed back in or not. What you need to be aware of when purchasing a cheaper BOV is that they often leak quite badly in between the piston and body of the BOV. We’ve pressure tested plenty of intercooler systems with replica BOVs on, and a majority of them leak like a sieve. Whereas with the genuine ones, you tend to never have a bad one. We think BorgWarner turbos with the BOV mounted to the compressor housing is a great idea, and they’re very effective and suitably sized for the turbo already.