swappedcx

I thought i had a .4 or .5 bar spring in and was a little suprised at the dyno when the car was hitting in the mid 11psi range with the boost controller off.

With the boost controller on today (blitz dual sbc spec-s) it peaked at 12.04 psi, and 12.10 psi...is that normal? the boost controller is off and doing nothing but being my boost gauge right now because my autometer gauge is wack.

nowtype

Your question makes no sense. What spring do you have? The title says .7 and in here you say .4 or .5. Use your head, take apart the WG, find out what spring you have, and then you will know if its normal or not.

swappedcx

use my head?

I said i THOUGHT i had a .4 or .5.

And wow what does the title say......7 bar. So apparently i already pulled it apart to find a .7 bar yellow spring

swappedcx

nevermind i already got help on the situation

nowtype

The answer is your boost gauge is reading absolute pressure and the WG works off gauge pressure. Two different readings. Tap your WG at the intake manifold and at the same location tap a regular old $20 boost gauge. I'd bet the WG will open around 10-10.5psi.

BoostedEG6

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nowtype &raquo;</TD></TR><TR><TD CLASS="quote">The answer is your boost gauge is reading absolute pressure and the WG works off gauge pressure.</TD></TR></TABLE>

That makes no sense ...... The boost gauge has nothing to do with the wastegate and how it opens.

The wastegate should be tapped at the intake manifold to achieve the proper mount of boost you want. The reason why is because if you tap at the turbo you will have pressure drop from the turbo to the manifold. You could be reading 10psi at the manifold and 11-12 at the turbo. I do agree with that part of your statement

nowtype

Go look up what absolute pressure is and what gauge pressure is. Then realize what I said is completely valid. http://www.google.com is your resource. Have fun.

wantboost

iTrader: (2)

um, ok you tool.

absolute pressure at seal level would be 14.7 psi so a gauge calibrated to show absolute pressure would show 14.7psi.. not 0... gauge pressure reads the amount of pressure ONTOP of absolute pressure. so 14.7psi absolute on a gauge calibrated to read gauge pressure would show 0.

so if his gauge were reading absolute.. he would be seeing right around 24.7psi.

go back to school

BoostedEG6

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Atmospheric pressure is the pressure exerted at the surface of a body by a column of air in an atmosphere. The pressure varies both with altitude, and weather patterns. Standard is an average atmospheric pressure at sea level, and is defined as 1 atmosphere on Earth, equal to 760 millimeters of mercury (760 Torr) and 101,325 Pascals.

The pressure of a system measured by a gauge, which excludes atmospheric pressure. Gauge pressure is sometimes also called overpressure. </TD></TR></TABLE>

before you try to call someone out do your own research

a boost gauge reads the same as the wastegate is seeing

EK k kay

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nowtype &raquo;</TD></TR><TR><TD CLASS="quote">Go look up what absolute pressure is and what gauge pressure is. Then realize what I said is completely valid. http://www.google.com is your resource. Have fun.</TD></TR></TABLE>

lol @ you

nowtype

Holy christ, you guys aren't making the connection. Its simple. Lets say the absolute pressure is .9bar. Well take this .7bar WG. Its going to open at 1.6bar absolute pressure. That means it will show 8.5psi on any electronic boost gauge. A regular boost gauge assuming its tapped from the same source will show .7bar or 10.15psi. See the difference? They are reading two entirely different pressures. The only time an electronic boost gauge will read close to the same is assuming is properly calibrated and you're atmospheric pressure is 14.7psi. Well thats less than likely, so a simple mechanical boost gauge will be a much better tool to use. Understand now? Never once did I claim it would change what the WG was doing or anything of the sort. I was trying to invoke some thought and understanding that you have to use the correct gauge in order to get the correct reading. Get it now? Or should I go back to school? Or should we all just yell and scream at Tial for making a wastegate that probably opens at damn close to 10.15psi and he is just using the wrong gauge to monitor it and probably has his vaccum source to the WG pre intercooler.

wantboost

iTrader: (2)

im not even going to try to start tonight./ too tired. tomrrow

swappedcx

my vacuum sources are right, and then apparently im using the wrong boost gauge from the dyno, my blitz boost controller, and my autometer gauge are all reading the wrong boost?

NJIN BUILDR

Are you talking a peak number or constant.Many manifolds will "spike" to a high number and settle down to close to your spring rating.Befere and after the intercooler will show a very different number sometimes.