Hi, does anyone have the factory Gauge cluster where the clock goes? Does anyone know how to read the boost on it? it starts at .05 and goes up but im not sure now to read it and how to convert it to PSI.

Oh yeah. My friend wsa working on my engine and did a sloppy job on it. The wires look all messy and watever. Can someone send me a pic of their engine bay? Like a nice clear pic of the entire engine bay. Much appreciated. My email is echun2049@yahoo.com

 

the boost gauge is in megapascals (MPa)

here is the basic conversion 0.1 MPa = 100 kPa = 1 bar = 14.50377 psi

 

or here is a list you might want to remmeber

0.1 MPa = 14.5 psi
0.09 MPa = 13.05 psi
0.08 MPa = 11.6 psi
0.07 MPa = 10.15 psi
0.06 MPa = 8.7 psi
0.05 MPa = 7.25 psi

 

thanks... that was exactly what i needed. I still need a pic of the engine bay though. So anyone with a pic and the time, please email me with it. thanks a lot.

 

just did a quick google search, heres a picture of a stock engine

 

thanks for the help. it was exactly what i needed.

 

The gauge is actually a "manifold pressure gauge". It shows the pressure in the intake manifold relative to atmospheric pressure. So, "0" corresponds to atmospheric which is what you see when the engine is off. In a normally aspirated car that's all you would see at full load.
Readings less than 0 indicate vacuum, this is what you will see at idle, light throttle/loads, coasting and deceleration.
At higher loads and throttle, the turbo will pressurize the manifold and you will see positive pressure or boost.
Hope this is helpful.

 

similar to what mulder said, anything that reads negative is vaccuum pressure. boost reads as the pressure that the turbo is pushing air into the intake manifold, when it is negative that means the turbo is not forcing air into the engine, but there is a negative pressure sucking air into the engine, as this is how NA cars work. some NA cars you will see people put vaccuum pressure gauges. a lot of aftermarket boost gauges will show that negative pressure as vacuum

 

The factory WRX boost gauge reads in mPa (megaPascals), not bar, although they are similarly easy to read. Look at the dial face and you will see that it reads as fractional numbers. 0.10 kPa is roughly equivalent to 14.7 psi or atmospheric pressure. Any value above 0.0 is considered boost pressure.

Here's a chart that explains more clearly why an engine (non-turbo) produces different vacuum readings under different conditions. Turbo engines produce similar readings when not under boost. Don't pay much attention to the numbers on the gauge faces in the chart, but the relative position of the dial pointer.

Further information can be found by doing a Google search.

--
0==WW==0
"…axles of evil…" - george w. bush

 

wrong, 0.1kPa doesn't = 14.7 psi

14.7 psi = 1.000276 atm = 1.013 bar = 101.35 kPa = 0.101 MPa

0.1MPa = 100kPa = 1 bar = 14.5 psi <--- i think thats what you meant to say

 

Noted, thanks for correcting my error.

--
0==WW==0
"…axles of evil…" - george w. bush

 

no problem, we all get units mixed up now and then