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Maeda
03-21-2004, 10:38 PM
Ok at idle my KA-T has always been at -10 vac.
http://forums.freshalloy.com/images/graemlins/confused.gif http://forums.freshalloy.com/images/graemlins/confused.gif
Whats everyone elses look like? I've heard it's SUPPOSED to be around -20 psi.

I tried looking for leaks in my system, and after a couple hours and a full bottle of carb cleaner I can't find diddly.
I put my BOV (SSQV) on full tight.

I also tried pressurizing i/c pipes with an air compressor and I hear a hissing sound comming from the rear passenger side of the engine.

The intake manifold is missing a nut on this side aswell...

My wastegate is openning at 2.0 psi... but the spring is set at 4.35

When I step on the gas slowly in Neutral, my vac goes up from -10->-8(1000->2000rpms)
and then it starts to go back down to -12 (2000-4000rpms)

Do I indeed have a vac leak, or am I just unique?

Blurple240
03-21-2004, 11:33 PM
I idle between 19" and 20". It sounds to me like you have a leak.

-john

Jeff240sx
03-22-2004, 12:08 AM
I run -22psi. And as I told you, I think you have a leak.
-Jeff

Maeda
03-22-2004, 03:35 AM
I run -22psi. And as I told you, I think you have a leak.
-Jeff


I'm pretty sure I do too but WHERE!?

not the i/c pipes
not the bov
not the vac hoses

I can hear the wastegate openning and shutting with the air compressor attached...

I'm thinking it might be the intake mani to head?

revlis240
03-22-2004, 04:09 AM
if you hear a hissing, then thats bad! haha, open up the throttle plate and then pressureize the system again. FIND THAT HISS and youve found your problem

-Abe

asad
03-22-2004, 08:01 AM
I run -22psi.



Wow, -22 psi! That's below a complete vacuum http://forums.freshalloy.com/images/graemlins/smile.gif

Asad

Jeff240sx
03-22-2004, 12:28 PM
I run -22psi.



Wow, -22 psi! That's below a complete vacuum http://forums.freshalloy.com/images/graemlins/smile.gif

Asad



Doh. Neglected to notice vacuum was in/Hg, and positive pressure was psi. Which is -10.8psi... http://forums.freshalloy.com/images/graemlins/tear.gif-
Jeff

Maeda
03-22-2004, 01:04 PM
im running -10.5 PSI ~ -11.0 PSI so I guess my leak isn't that bad. =)

asad
03-22-2004, 01:18 PM
Doh. Neglected to notice vacuum was in/Hg, and positive pressure was psi.



I'm gonna nitpick some more -- the unit of vacuum is actually inHg, not in/Hg (inches of mercury vs. inches per mercury).

Asad

McGuirk
03-22-2004, 01:29 PM
Damn Asad you are picky, I love it so much! http://forums.freshalloy.com/images/graemlins/grin.gif

revlis240
03-22-2004, 02:53 PM
you have a vacuum gauge that reads in PSI? i have never seen that...what kind is it?

-Abe