hey all,
I was wondering if I have a boost leak or is this normal.
I have a defi boost guage and at idle it reads -10 lbs. But the moment when I engage the clutch to shift up while driving, the meter goes down to -20. I'm curious to know if this is normal or if I need do do a boost leak test.
Any help is appreciated!Thanks.

 

You should do a boost leak test anyway. It's always good to make sure everything is tight and that there are no leaks.

Realistically, it doesn't take long to do the test. The hard part (might) be fixing the leaks.


Also, FWIW - some leaks you can't notice and in your case, even if you could tell (tell tale sign is loss of power, spool up and over-boosting) you would have to be in boost (greater than 10 PSI, not in the 'negative' (vacuum) region to which you were referring).



-Bink

 

that is vacume and if you idle is getting rough you might have a vacume leak but i tto would suggest a boost leak test not hard to do at all good luck

 

where can i get the parts ONLINE for a boost leak tester?

 

You can go to home depot and buy everything from there.

otherwise check this out:
http://www.siliconeintakes.com/index...eeace4c9223499

 

^ Alrite thanks a lot, also i would put this directly on my turbo? whats the inlet size on a fp black? 3.25?

 

thanks all, Ill go ahead and do a boost leak test soon.

 

^^bump for an answer!

 

This is completely normal. The higher rpm of the engine + closed throttle plate produces greater vacuum than at idle.