A friend of mine is saying that BOV’s increase horsepower (with nothing else done at all) on a forced inducted motor where I’m saying it does not. If you have 2 stock turbod engines from the factory, one equipped with an aftermarket BOV and the other with either a stock one or none at all, you wont see any difference in numbers at all. He thinks I don’t know what I’m talking about.

 

He hasn't a clue of what he's talking about.

 

A BOV holds/releases pressure. It does not generate power.

 

my friend told me that on his 02 wrx that an aftermarket (atmospheric) bov would release too much pressure resulting in the slightest decrease in hp.



idk if it's true but to me bov's are a rice mod.

 

aftermarket BOV + 5 hp



e-bay performance chip + 60 hp



Tornado intake thingy + 15 hp



people that believe that crap - priceless

 

This is a case that you get what you pay for. If you buy a cheap ebay knockoff BOV that leaks then yes you'll lose boost pressure which will decrease horsepower. Same holds true the other way around. If you have a leaky BOV from the factory and you replace it with a high quality aftermarket one that doesn't leak, you will see more steady boost pressure that may increase horsepower. Or if your increasing the PSI level beyond what a stock BOV can handle then a stronger BOV will help you hold more pressure which will create more power.



Bottom line is its not the BOV itself its the BOV's ability to hold pressure that can increase/decrease power.

 

^^Well stated.