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Ran a VAC test, help with results.

  • Thread starter Thread starter Rerun
  • Start date Start date Aug 27, 2004
R

Rerun

Founding Member
Mar 31, 2002
312
0
16
South Bay, California
Aug 27, 2004
#1
  • Aug 27, 2004
  • #1
So I bought a guage for the hell of it to see what I'm getting. I've got a pretty big cam in the thing, it's pulling around 14" sometimes a little lower. The needle seems to bounce with the lope of the cam. When I give it a little gas the vac jumps to around 20+. Is this normal or do I have an issue somewhere.

Just for some notes, I hooked the vacuum guage between the EGR section of the intake manifold and the EGR vacuum regulator.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Aug 27, 2004
#2
  • Aug 27, 2004
  • #2
im not sure i follow - the EGR vac is puter controlled. it works a little differently than manifold vac.
i would get vac off the vac tree on the firewall. stockish motor should have 15-20 inches at idle (less with cam).

the vac will decrease as you mash the gas (at WOT, vac is almost 0).

good luck.
 
R

Rerun

Founding Member
Mar 31, 2002
312
0
16
South Bay, California
Aug 27, 2004
#3
  • Aug 27, 2004
  • #3
There's a vacuum line that comes from the back of the intake manifold to the egr vacuum regulator. From what I understand there's constant vacuum to that, the regulator opens up the second tube which is connected to the EGR and sends vacuum as needed.

I'll try and pull from a tree later. I did a search on the forums for vacuum results doesn't seem like 14 is too bad for a car with a pretty big sized cam in it.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Aug 27, 2004
#4
  • Aug 27, 2004
  • #4
ok, i gotcha. sorry about that. i would say 14 is just fine.
 
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