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02'psd U7170 Base NOV?
Posted: Wed Jul 22, 2009 7:39 pm
by msc42783
U7170 on an 02' PSD. I went into modify tunes to adjust my tire size for the transmission shift points. I run 35'' tires, do I do this under axle ratio? It says base NOV, what is that?
RE: 02
Posted: Thu Jul 23, 2009 10:41 am
by SCGt94
Base NOV iis the ratio the PCM will use when calculating shift points in MPH. NOV is Engine RPM divided by the vehicle speed in MPH when the transmission is in a 1:1 gear (usually 4th gear of a manual or 3rd gear of an automatic). The parameter represents for every Base NOV RPM's, the vehicle speed will increase 1 MPH.
NOV = (Tire Size * Axle Ratio)/60, use that then punch in your answer into the predator.
RE: 02
Posted: Thu Jul 23, 2009 10:50 am
by SCGt94
and in order to get tire size for that formula use..
tire size = 20,850/{(2*section width*aspect ratio) + wheel diameter} (in inches)
but since thats kind of annying use this
http://www.miata.net/garage/tirecalc.html
your interested in "revs/mile" which = tire size for the first formula i sent you.