Since 1994, both GReddy and HKS have been creating aftermarket blow off valves for turbo car tuners. Although they essentially do the same work and complete the same task, there are many differences between the GReddy Type RS BOV and the HKS SSQV BOV. Each have their own set of advantages and disadvantages; however, many turbo tuners trying to decide between the two blow off valves always seem to be torn on which on they should buy.
To help out the decision of which one to buy, here is how the GReddy BOV and HKS BOV compare with each other, in both the BOV sound and performance.
To many people, the sound of the blow off valve is the most important part. When they cruise down the street, they want to be able to shift and have the sound effect enhance the look and quality of their customizations, so having a quality blow off valve sound can really catch people’s attention and make a statement.
The GReddy Type RS BOV releases its extra air pressure slowly, causing it to sound like air blowing. There really isn’t a loud sound, rather a subtle burst of air, which sounds exactly like air coming out of an air compressor. For many people, this just isn’t “cool” since it isn’t loud; however, sometimes staying “low key” isn’t exactly a bad thing, especially when you are driving on cop infested streets.
On the other hand, the HKS SSQV BOV can actually be three different sounds. You can either have no insert, a three arm insert, or a circular insert, which goes in front of the blow off valve’s release port of the valve. Leaving the inserts out allows you to have a quite sound, like the GReddy Type RS BOV has, while putting in either insert will allow you to have two very distinct and performance BOV sounds.
The two blow off valves perform very differently, even though they complete the exact same task. The GReddy Type RS BOV works with a “push” valve, which allows the air extra air pressure to simply push out of the valve, once it reaches the valves threshold. This design is used in many blow off valves; however, it does leave the possibility of the valve leaking and giving a slow release.
The HKS SSQV BOV is designed completely different, as HKS wanted to design a “pull” valve system, which uses two valves and alternating pressures to pull open valves, in order to release excess pressure. This system is highly effective, as it prevents any leaking and gives off one solid burst of air releasing, as soon as the valve does open.