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gsmith660 gsmith660 is offline
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Join Date: Jun 2007
Location: Missouri
Posts: 4,183
Mark thanks I was kinda thinking that way but I wanted confirmation from someone who knew I have a couple things left to take off and check for leaks and then I guess I have to take the intercooler up and get it pressure checked.

Originally Posted by mark houghton View Post
That diaphram in the WG hooks to the valve stem, pulling it off it's seat (against the WG spring tension) when the diaphram is pressurized by the boost signal. The valve runs through a guide, and it's the guide that will allow some air to pass by it. So if you're applying vacuum to the boost port on the WG, you won't be able to hold it due to the air coming in through the guide.

It's not such an issue when you're applying oodles of boost air volume...that small amount of leak-by isn't a concern until the guide wears badly enough to where you can't sustain pressure in the diaphram, resulting in the WG not opening quick enough and creating boost spike issues....the reverse of the symptoms you're experiencing.

Probably a poor description, but something like that anyway.
" Porsche there is no substitute" I always liked that saying. Air cooled is the only way to go!
76 911 C.R.A.P. Gruppe #2 BIG time TURBO C.R.A.P. Bitz EFI/EDIS Now MegaSquirt 3
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Last edited by gsmith660; 05-01-2013 at 04:32 PM..
Old 05-01-2013, 04:27 PM
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