What's the +40 on an FC boost gauge mean?
#1
pfft.
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What's the +40 on an FC boost gauge mean?
Yeah, read the title. I've never seen boost measured in this way. What's it stand for, and what's +40 in psi/bar? Thanks.
#2
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It does say pretty clearly on the gauge that the scale is x10mmHg (times ten millimeters of mercury), so it reads from -200mmHg to +400mmHg. 1psi = 51.7mmHg so full scale is ~7.7psi.
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Originally Posted by TetsuKatana
Hmm... mine never goes up that high... at WOT it only hangs around the middle of the gauge... is something messed up?
Originally Posted by slpin
its not suppose to max out...
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My car is stock, but it's only started hitting the + on the 40 since i got a straightpipe. Boosts a lot more. I'm not complaining. If it's only at 7.7, or so, I'm not gonna hit fuel cut any time soon, so I'm safe. Thanks.
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#8
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Originally Posted by NZConvertible
Do you have a proper boost gauge to compare it to? Since you're obviously expecting more than stock boost you definitely should have one.
In a stock car maybe, but if you boost high enough (i.e. over 7.7psi) it certainly will...
In a stock car maybe, but if you boost high enough (i.e. over 7.7psi) it certainly will...
true enough! i was assuming he has a stock car.
#9
means get bigger turbo and boost controller and boost gauge
simply complex. you need to memorize my car more. jk. terry has your email at work so
I can't send anything till monday. how did you like the hood on saturday? pm me to get info
simply complex. you need to memorize my car more. jk. terry has your email at work so
I can't send anything till monday. how did you like the hood on saturday? pm me to get info
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lol mine reads a few pounds of vacuum when the engine is off (guess what, they arent too accurate)
not to thread jack, but what is stock boost?
for clarification, it reads a few pounds vacuum when they key is in the on position, but the engine is not running
not to thread jack, but what is stock boost?
for clarification, it reads a few pounds vacuum when they key is in the on position, but the engine is not running
Last edited by Secondmessiah; 09-24-06 at 08:21 PM.
#11
Sharp Claws
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and if you have a FCD that gauge will be almost completely useless since the signal from the pressure sensor will be altered.
the only thing the stock boost gauge is good for is seeing if you actually are producing boost, aside from that the readings are hardly accurate even when it is working right.
the only thing the stock boost gauge is good for is seeing if you actually are producing boost, aside from that the readings are hardly accurate even when it is working right.
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Originally Posted by Secondmessiah
lol mine reads a few pounds of vacuum when the engine is off (guess what, they arent too accurate)
not to thread jack, but what is stock boost?
for clarification, it reads a few pounds vacuum when they key is in the on position, but the engine is not running
not to thread jack, but what is stock boost?
for clarification, it reads a few pounds vacuum when they key is in the on position, but the engine is not running
#13
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Originally Posted by SimplyComplex
My car is stock, but it's only started hitting the + on the 40 since i got a straightpipe. Boosts a lot more. I'm not complaining. If it's only at 7.7, or so, I'm not gonna hit fuel cut any time soon, so I'm safe. Thanks.
#14
Originally Posted by Secondmessiah
lol mine reads a few pounds of vacuum when the engine is off (guess what, they arent too accurate)
not to thread jack, but what is stock boost?
for clarification, it reads a few pounds vacuum when they key is in the on position, but the engine is not running
not to thread jack, but what is stock boost?
for clarification, it reads a few pounds vacuum when they key is in the on position, but the engine is not running
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Originally Posted by Secondmessiah
not to thread jack, but what is stock boost?
Originally Posted by Karack
and if you have a FCD that gauge will be almost completely useless since the signal from the pressure sensor will be altered.
In the Paul Stokes FCD article, the unnamed aftermarket FCD reduced the MAP signal by ~8%, which would move fuel cut up to ~10.5psi.
Originally Posted by Johny zoom
For clarification vacuum is measured in inches of water column.
#18
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Personally I think the whole idea of rating wastegate springs at a certain boost pressure is silly. There are many, many other variables besides the wastegate spring that determine how much boost is made.
Anyway, the whole 5.5psi thing is a myth. The S4's stock max boost is 6.6psi as per the FSM, which occured at ~4000rpm IIRC at then started dropping.
Anyway, the whole 5.5psi thing is a myth. The S4's stock max boost is 6.6psi as per the FSM, which occured at ~4000rpm IIRC at then started dropping.
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