Originally Posted by MFwrx
Iv read that sone people have carried the stock bov up to 22psi no problem. Can you explain why a struggling bov would make that noise though? Like what's physically causing the sound I make during boost?
The stock bpv can go to 22psi on the STI because it is metal, but the WRX stock bpv is plastic and leaks at stage2+. Physically I cannot explain it, what does any other leak sound like though? It only happens when you are in boost, so I can only assume it is the BPV. I don't know how much power your pushing, but the stock intercooler will leak at higher power levels as well.