so how much do you guys pull at idle and on a stong decel?
(i couldn't find it on the tsrm :cry:, but i figured i would like to hear real world #'s)
(i couldn't find it on the tsrm :cry:, but i figured i would like to hear real world #'s)
vacuum?
- Thread starter black89t
- Start date
Mine runs about 24-25inches at idle, and pegs the gauge at 30inches on even light decels.
Is there such a thing as too much vacum, other than a clogged air filter or something along that line?
Is there such a thing as too much vacum, other than a clogged air filter or something along that line?
I never understood how the Vac could state the condition of the oil?! im guessing loss of vac from something with the oil control ring?
20-21 in/hg warm idle
18 in/hg with ac at idle
24-25 in/hg on decel depending on gear and rpms.
usually only snaps back to 24 or a bit less when the throttle is first closed. (I think the dashpot is hanging a bit causing this)
edit: label correction
20-21 in/hg warm idle
18 in/hg with ac at idle
24-25 in/hg on decel depending on gear and rpms.
usually only snaps back to 24 or a bit less when the throttle is first closed. (I think the dashpot is hanging a bit causing this)
edit: label correction
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Keep in mind the elevation for where you live has an impact.
Dumbo - Valve timing, restriction in the intake, IC, or piping. Your gauge could be FUBAR too
Dumbo - Valve timing, restriction in the intake, IC, or piping. Your gauge could be FUBAR too
dumbo;1308037 said:
Another guy who must be living on a different planet than the rest of us
Edit (for grim): comment deleted
jetjock;1308106 said:Another guy who must be living on a different planet than the rest of us
Venus? :biglaugh:
i'm wondering because i only see 22 in/hg on my tru boost at decel. even on a hard decel i only see 22 in/hg. on my old pile of shit eqaus or whatever its called it pegged the 30 in/hg.
no vacuum/boost leaks
good compression
i did tap into the line off the back of the intake. it has a T going to the tru boost then a line to another T that goes to the heater bpv and the stock boost gauge. is that too many things? btw the motor runs great. and i love the tru boost. screw mbc's and there shitty boost control.
no vacuum/boost leaks
good compression
i did tap into the line off the back of the intake. it has a T going to the tru boost then a line to another T that goes to the heater bpv and the stock boost gauge. is that too many things? btw the motor runs great. and i love the tru boost. screw mbc's and there shitty boost control.
You might have a small leak at the heater VSV...22 in/hg is not that low on decel for this motor. If you want to test, hook the TruBoost up direct.
I wish I was near my car and I would take a quick vid of it, boost hits about 8-9, I dont think the gauge is fubar, valve timing is good when I changed my intake cam, and it didn't change much after that either. I'll take a look at some of my maft logs after work if I still got them and confirm. And I'm pretty sure theres no restriction anywhere in my intake.
Does anyone peg their gauge on decels?(30inches??)
Being a 7M-GE with all GTE electronics make any difference???
EDIT: didn't you know it's a different world up here LOL hahahaha
Does anyone peg their gauge on decels?(30inches??)
Being a 7M-GE with all GTE electronics make any difference???
EDIT: didn't you know it's a different world up here
LOL hahahaha
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jdub;1308492 said:
Started NA cams, changed intake to GTE(exhaust is the same) didn't change the vacum much, which was a suprise.
Well according to my maft log labeled "precams"(only one I could find) I get about 2.6kpa on decel. I worked all night(I hate night shift) but if my math is right that is 32.11in/hg, please feel free to correct me if wrong.
19-20kpa @ about 700rpm(idle) which gave me 35.54in/hg...clearly my math is wrong:nono: I'm missing something with the absolute pressure... I think the highest I saw was 147kpa.(full boost)
:1zhelp:I'm quite curious on this now:icon_evil
) but if my math is right that is 32.11in/hg, please feel free to correct me if wrong.19-20kpa @ about 700rpm(idle) which gave me 35.54in/hg...clearly my math is wrong:nono: I'm missing something with the absolute pressure... I think the highest I saw was 147kpa.(full boost)
:1zhelp:I'm quite curious on this now:icon_evil
Dumbo - You must be reading vacuum kPa relative to absolute atmospheric (101 kPa)...from what I can cipher for the vacuum conversion from kPa (relative) to in/hg (gauge):
2.6 kPa = 29 in/hg
20 kPa = 24 in/hg
For pressure:
147 kPa = 21 psi
2.6 kPa = 29 in/hg
20 kPa = 24 in/hg
For pressure:
147 kPa = 21 psi
jdub;1308993 said:
Well the vacum makes sense, and confirms the gauge for the most part, but I'm certain it pegged the 30in/hg(autometer, basic gauge, 30inches-20psi) but that idle seems spot on.
the boost seems a little off lol, if the GE is taking 21 psi, it's handling it very well, and is pretty slow considering LOL. Vac source is off the back of the manifold, same one that runs my MAP, and my heater VSV. DM 57 CT-26 NO boost control...yet.
One day when I see my car again.. time for the manometer...
I found one quick video of me racing my buddy in his 240, and the gauge looks like it hit more like 7-8psi
Thanks jdub,
SORRY FOR THE THREAD JACK!!
Yet another victim of the death spiral in science education. It's not possible to obtain more than 30 in/hg on this planet and even if it were your engine couldn't do it...
QFT
Dumbo - I'm suspect of those readings for this reason...they are way too high for vacuum. 29 hg/in on decel would be impossible to obtain.
jetjock;1309034 said:
Dumbo - I'm suspect of those readings for this reason...they are way too high for vacuum. 29 hg/in on decel would be impossible to obtain.