PROMO Product Release - VTT Billet Vacuum Relief Valve


New Member
Jun 27, 2018
@martymil If you look at the photo of my vacuum gauge it says the inside lower reading is "in Hg vac" but am I correct that the marking is actually .5 not 5.0?

I ran it first with one shim and got a crazy loud resonance sound from the engine.

Right now it looks to be in spec at .6 or 14" just wanted to confirm with you guys on here with my reading attached


Sep 6, 2017
Down Under
yes thats 5.5 inhg the outside is 14cmhg so within spec what vtt recommends.

Stock is 17 mbar or 0.5 inhg or 1.2 cmhg

I personally can't run anymore than 2 inhg without one of the seals whistling like crazy

I see it this way as long as you run anything higher than stock without seals whistling you will be ok.
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