The stock BOV on the X is known to leak at 25psi. A lot of guys crush theirs because the aftermarket BOVs have been a real crap-shoot...the vast majority being worse than stock when it comes to drive-ability.
I decided to pick up a Coto sports BOV-MO4. It is a stock BOV with a stronger spring. A guy that has one says it holds to at least 30psi and behaves like stock.
The obvious downside: JDM pricing yo!
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