The stock 3/S BOV usually leaks, so it doesn't surprise me that your boost rose a bit. But it shouldn't be at 15psi, unless you have a boost controller. Maybe your gauge is off. What other mods are you running?
As far as hitting the counter weight.... I used a zip tie and tied the BOV over to the hard line running under the MAS. I use the 1g DSM BOV on both my 3/Ses. They work great.
You should really be on MN 3/S:
http://mn3s.zforcenetwork.com/index.php We don't bite.
later,
Curt
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