Can 2 BOV's cause a boost leak on a single turbo set up?
 

Hi everyone I just bought my first supra a few weeks ago. It is a 1995 mk4 targa top. When I bought the car it already had a Garrett 67mm turbo and an HKS intercooler. Long story short I took it to my buddies shop to get it tuned and we discovered that after 9lbs or so of boost it would leak boost. We checked out the piping and it was all good to go but noticed while inspecting the turbo piping that the car has 2 blow off valves. Could this be the reason I am leaking boost? I went from a civic to a supra so any help would be appreciated.

It is unlikely that the BOVs are the source of the boost leak but it is possible. You need to pressurize your intake system. This is done with an air compressor, and typically a jury-rigged adapter - usually with hose clamps, plumbing supplies, and an air valve. Your intake system should hold 25psi at least ... if not, you'll hear where it is leaking. The pros use a smoke machine, and pressurize the intake system with smoky air so you can hear and see the leak(s).

Please let me know if you have any questions.

HI i have seen a bov leak more then once but usely cheap ones

Unfortunately, the OEM BOV often leaks after 50k+ miles of exposure to the heat of a turbocharged engine bay. This is one of the few areas it seems the Toyota accountants beat the TRD engineers in selecting components for the Mkiv Supra Turbo.