MAP reading 25 @ WOT?
06-30-2004, 03:12 AM
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MAP reading 25 @ WOT? Does anyone know what could cause this? 
FTC 15 and 22 show readings of up to 25. I know from looking at others A-TAP logs that it should be around 15. Thanks for any ideas.
Jeremy
FTC 15 and 22 show readings of up to 25. I know from looking at others A-TAP logs that it should be around 15. Thanks for any ideas.Jeremy
06-30-2004, 08:54 AM
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10lb of boost, or a bad MAP sensor? If you are WOT
at 3000-4000RPM you should be seeing atmospheric
pressure (less than 14.7PSI at higher altitudes). Or
about 100kPa, but I don't think that's what you're
talking about.
You're sure it's Manifold Absolute Pressure (or
whatever ATAP calls that PID) and not something
else getting logged?
at 3000-4000RPM you should be seeing atmospheric
pressure (less than 14.7PSI at higher altitudes). Or
about 100kPa, but I don't think that's what you're
talking about.
You're sure it's Manifold Absolute Pressure (or
whatever ATAP calls that PID) and not something
else getting logged?
07-01-2004, 01:44 AM
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I am positive. There are two MAP PID's being logged on A-TAP. One is in (in Hg) and the other is in (kPA). The kPA is logging 86 at WOT while the (in Hg) is 25. I have used search but could only find what it should be but no solutions.
Jeremy
Jeremy
07-01-2004, 09:19 AM
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OK. InHg is about 30 for atmospheric pressure.
You would want to scale that by the BARO
value to get an idea of how "intake efficiency"
is, since your elevation is probably way off from
what I'm used to (or get it off the weather report).
Like, you want MAP(WOT)/BARO as close to 1.0
as possible on a NA car. Any drop from that ideal
represents potential power from intake tract mods.
So look for a BARO (baseline barometric pressure)
PID and see if you can pick that off too, and use
it to scale the MAP to a 1.00 (100%) basis in Excel.
You would want to scale that by the BARO
value to get an idea of how "intake efficiency"
is, since your elevation is probably way off from
what I'm used to (or get it off the weather report).
Like, you want MAP(WOT)/BARO as close to 1.0
as possible on a NA car. Any drop from that ideal
represents potential power from intake tract mods.
So look for a BARO (baseline barometric pressure)
PID and see if you can pick that off too, and use
it to scale the MAP to a 1.00 (100%) basis in Excel.
