inHg conversion to psi question
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OVERDRIVE
Joined: May 2003
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From: Greensboro, NC
inHg conversion to psi question
This questions is for those of you who paid attention in physics class. If my OBD is telling me that my maximum intake manifold pressure is 52 inHg, how many PSI am I getting?
Thanks
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6th Gear
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From: Phoenix, AZ
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From: A Den in Maryland
The pressure reading is given in absolute, not gauge pressure. You have to deduct atmospheric pressure at your location from that reading. Also, the maximum reading may be a bit suspect, because according to to my service literature, the MAP sesnor on the MINI has an upper limit of about 18PSI, and with my experience with similarpressure sensing devices in industrial control and measurement applications, once you reach the limit of a particular sensor, it no longer gives a linear output beyond it's range; it will continue to register an increasing pressure, but at a declining rate till it either 'pegs' or becomes damaged.
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OVERDRIVE
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From: Greensboro, NC
Originally Posted by Greatbear
The pressure reading is given in absolute, not gauge pressure. You have to deduct atmospheric pressure at your location from that reading. Also, the maximum reading may be a bit suspect, because according to to my service literature, the MAP sesnor on the MINI has an upper limit of about 18PSI, and with my experience with similarpressure sensing devices in industrial control and measurement applications, once you reach the limit of a particular sensor, it no longer gives a linear output beyond it's range; it will continue to register an increasing pressure, but at a declining rate till it either 'pegs' or becomes damaged.
So pardon my laymen logic but would I then subtract 14 from 25 and get 11psi? I'm at around 600 ft from sea level...Crap...that means my pully doesn't work
6th Gear
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From: Lansdale, PA
Check your reading with the key on, engine off. That should give you the ambient pressure. Then go out and do a WOT pull from 2k-redline. Subtract your ambient and there's your boost reading.
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OVERDRIVE
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From: Greensboro, NC
Originally Posted by andy@ross-tech.com
Check your reading with the key on, engine off. That should give you the ambient pressure. Then go out and do a WOT pull from 2k-redline. Subtract your ambient and there's your boost reading.
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