Photo by Erik Mclean on Unsplash

Blow off valves protect your turbocharger, and by extension your engine, by relieving pressure and helping to prevent compressor surge. In other words, they’re a vital part of any system running boost. Unfortunately, their prevalence in the turbo community has led to a collection of myths that can be at best amusing, but at worst, seriously damaging. Today we’re going to bust some of these myths.

Myth: The Factory Blow Off Valve Is Good Enough

Reality: If you’re just driving around peacefully in your stock-standard, factory-turbo car, the factory blow off valve will probably be good enough to get the job done. However, if you’re the type who likes to have a bit of fun behind the wheel, or you’re looking to add some extra boost, it’s a good idea to look into the best blow off valves online and get an upgraded one that better suits your needs.

The factory fitted options are designed for operation under “standard conditions,” which is highly subjective and, therefore, not a good measure of when it’s time to upgrade. As a general rule, you’re better off safe than sorry, so if you’ll be pushing your engine or making modifications, you should probably get a better valve.

Myth: The Blow Off Valve Creates The Signature Whoosh Sound

Reality: While your blow off valve *may* be responsible for your whoosh noise in that the air being released through it creates the sound, a blow off valve doesn’t necessarily mean you’ll get sound effects. In fact, some blow off valves vent internally which allows for super-quiet operation and no whoosh. This is common with many factory-fitted valves as they’re designed to reduce noise pollution.

Whether you want this sound or not is a matter of personal preference, but if you’ve been avoiding getting a blow off valve because of it, you can put your worries aside since you most likely already have one, it’s just hiding. When deciding whether to switch it out or not, refer to myth one.

Myth: Blow Off Valves Boost Horsepower

Reality: In some cases, you might see increased performance with the installation of a blow off valve. This doesn’t mean, however, that your new friend has increased your horsepower. Blow off valves can help increase the efficiency of your system by reducing the risk of turbo flutter and compressor surge, but they don’t directly affect anything mechanically.

Myth: Blow Off Valves Can Be Applied To Any Car

Reality: Blow off valves are only used with turbocharged vehicles. If you are trying to emulate the whooshing noise, a sound kit can be purchased for a standard vehicle. However, if you are looking for assistance with performance, blow off valves serve no purpose for a non-turbo car and can’t actually be applied to one successfully.

Myth: Blow Off Valves Damage Engines

Reality: A properly installed and functional blow off valve cannot damage your engine. They’re designed to improve the performance and safety of your turbocharger, and as such will not cause any issues. The failure of a blow off valve may result in damage. However, this is not damage attributed to the part, but rather to the breakdown. This is rare in properly fitted and maintained parts, but if you think your blow off valve may have an issue, it’s probably time to replace it.

So there you have it, five common myths about blow off valves – BUSTED.