Diesel Math

[Alf]

Help, I can't seem to find a formula for converting Kpa to PSI.
I had the opportunity to use a snapon scanner on a long drive. Boost only read in Kpa or Inches of mercury.
Thanks

[jlog]

1 PSI = 6.894757 kilopascal
1 KpA = .1450377 PSI

john
ps I have a small metric converter file if you are interested

[jlog]

here is a neat website for common conversions also
http://www.super-kids.com/metric_converter.htm

john

[whatnot]

There might be a menu to switch from metric regular.
My old OTC does.

[Alf]

Hmmm
Something isnt right then. I saw a peak if 165Kpa(23.9psi?) cruise@ 75 mph was about 140Kpa 20
psi ? All the above with a 7K lb trailer, aprox 65* F.
I'm going to hook uo the scanner again and go for a drive.

[Billman]

I think you have to subtract 1 atmosphere(?) from your value(14.7).
That would put you in the ballpark 5-9psi.

Somebody correct me...

[ 06-15-2004, 09:43 AM: Message edited by: Billman ]

[Alf]

Just got back from the test drive, 90Kpa without the engine even running led me to beleive the same thing. Subtract One atmosphere, at my altitude is 90 Kpa or 13.03 psi. Peaked on this drive at 170 Kpa so that puts me at a peak boost, more of a spike, to 11.9 psi.
when crusing at 140 Kpa that would be aprox 7 psi.
Thanks for the help!!

[Ken Finchum]

You need to subtract the baro reading from the boost reading to get boost increase.

[Turbine Doc]

Go here it's plug n convert

http://www.onlineconversion.com/

[JohnC]

100 kpa is roughly 15 psi which is approximately sea level atmospheric pressure. so, e.g. 130 kpa is roughly 1.3 atm or 4.5 psi boost. Very rough, probably +/-1 psi unless you're in the mountains.