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How much vaccuum?

0
Aug 15, 2008
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Hey everybody,

I've got a 2008 Apex with an MCXpress 290 kit installed running 17lbs. I'm just curious how much vac the throttle body lines should be producing. I got a new Turbosmart Veeport blow off valve to replace the one included in my MCXpress kit. When I had everything hooked up, I was just curious to see how much vac the sled would pull, so I started the sled up with my finger over the line, and when i pulled it off there isn't really that much vacuum at all. I'm wondering if this is why I was getting some turbo flutter and the old blowoff might not have been lifting at all.

The sled didn't even change in RPM when I would take my finger off of the hose and put it back on. There is a slight vac, but not much. However, the apex runs like a freakin dream and I have no issues other than just that question... Any help would be appreciated. Thanks.
 

Polarisrocks

Well-known member
Lifetime Membership
Sep 22, 2002
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Eastern Wa
the sled should chugggg and almost die if you pull a vaccum hose open. It should throw a code 14 too. At least the three I work on have some vaccum. mine has a shim and it idles at 12-14 inches of vaccum and when you chop the throttle on it you can see 20 plus inches.
 
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Aug 15, 2008
93
0
6
41
thanks for the replies. I am going to get a vac gauge, and next year just before I take it out I will measure what it makes at idle. There is some vac there, I just want to make sure that my BOV opens when I let off the throttle.
 
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