BOOST/VACUUM CONVERSIONS [Mpa, bar, atm, psi, inHg)

[PlatinumWRX]

This question seems to come up a lot, so I figured I would put it in it's own thread.

Manifold Air Pressure (or boost/vacuum) can be measure in a variety of units, these include MPa, bar, atm, psi, and inHg (inches of mercury). If I left anything out, let me know, but I think I covered all of the usual suspects.

0.1 MPa = 1.0 bar = .987 atmospheres = 14.5 psi = 29.53 inHg

These are the real unit conversions from .1 MPa to all the others with minimal rounding.

1 atm = 14.7 psi for further reference.

When the boost gauge reads 14.7 psi, that mean that you have twice the nominal atmospheric pressure available to your intake valves. When the gauge reads 0 you are at atmospheric pressure. When the gauge reads negative, you engine is drawing a vacuum on the intake manifold, just like a naturally aspirated car always does.

I hope this clears up any confusion for our members that are new to the world of turbocharging.

-Jim

p.s. A Pascal (Pa) is the metric unit for pressure equal to 1 Newton of force distributed across 1 square meter of area (N/m^2). A MegaPascal (MPa) is 1 million Pascals or 1,000,000 Newtons / 1 meter^2.

[masanz1]

MPa/0.00689476=PSI

i.e

.1 / 0.00689476 = 14.5PSI

[NJSubieTech]

A great sight that will do pretty much any unit conversions you need - to as much accuracy as you need them:

http://srd.yahoo.com/goo/scientific+...sion+tables/1/*http://www.convert-me.com/en/

Speed safely,

Joe

[nuthinspecial]

Here is a converter I mentioned in another post. It will convert about anything.

ftp://ftp.wsdot.wa.gov/public/Metrics/convert.exe

Sorry for the double post, not sure how to link back to the other.

Bill

[TypeC]

another good link for any type of conversion

http://www.digitaldutch.com/unitconverter/

[KurleeDaddeeWRX]

Here is also a very good conversion website. Since Bar and hkPa are the same.

http://www.worldwidemetric.com/metcal.htm

Kurlee Daddee
(THE ORIGINAL)