Which blow off valve kit do you recommend for an MY98 WRX with a cat back exhaust and pod filter? Everything else is standard.

It all depends on how loud you want it! Our range includes a full plumb-back valve for silent operation, the twin trumpet Bovus Maximus for maximum noise, or the Hybrid, which offers the best of both worlds. For the best versatility, we recommend the Hybrid. Due to the modular design of GFB blow-off valves, it can easily be configured (using a supplied plug) for vent-to-atmosphere operation, or as a plumb back to solve any airflow meter related problems or excessive BOV noise issues. All of these valves will fit directly onto the factory blow off valve hose on the MY98.