NZ951

Atmosphere is 14.7 psi, not 14.5 psi as well... IIRC.

Oddjob

Yep, 14.696 psi absolute pressure at sea level. As you go higher in elevation, the atmospheric pressure decreases. So atmospheric pressure is not 14.7 psi in Denver.

Absolute pressure gages indicate exactly that, absolute pressure. The stock boost gage in a 944T indicates absolute pressure in Bar (the conversion is stated above, its around 1.01 Bar = 1 atm = 14.696 psi). This is actually not a very common way to refer to boost pressure.

More common is to refer to gage pressure or the differential pressure between the manifold pressure and atmospheric pressure. Many gages are differential pressure gages and indicate the pressure above atmospheric.

So when you hear someone talking about running 15 psi boost, that is 15 psi above atmospheric, or 15 + 14.7 psi (at sea level...) = 29.7 psi absolute pressure. But dont use the absolute convention, it will just confuse people, unless you are talking to other 944T guys about the stock boost gage.

Scootin159

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