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question on psi in kmanager 1.4.1

Posted: Thu Oct 14, 2010 6:27 pm
by uncledan
When I view a datalog on 1.4.0, that was created on 1.4.0, I see psi as high 11.9. The same datalog viewed on 1.4.1 shows pressure of 11.6 at the exact same location on the datalog. 1.4.1 is reading psi .3 or more lower than 1.4.0. through the whole datalog.

Is this correct based on the "What's new" entry of 1.4.1 correcting a ~1.2 % error of older versions? Seems more like ~3%. Am I missing something?

For what its worth, I am running an Omnipower 4 bar map sensor and Jackson Racing Supercharger.

Posted: Fri Oct 15, 2010 9:18 am
by Spunkster
That is the correction that is listed in the newest version.

Posted: Fri Oct 15, 2010 2:03 pm
by uncledan
I understand that. However, the correction seems to be more than ~1.2 percent, more like ~3 percent.

Posted: Mon Oct 18, 2010 11:01 am
by Hondata
1 - ((14.7+11.9) / (14.7+11.6)) = 1.14%

Posted: Wed Oct 20, 2010 6:50 pm
by uncledan
Welllll, using that calculation its 1.14%. But on the datalog, the difference is around .3-.4 psi which is about 2.5%.

11.9-2.5%=11.6025 guess its all in how one does the math.

Thanks for explaining.

Posted: Wed Oct 20, 2010 6:56 pm
by Hondata
No, the difference between 11.6 and 11.9 of pressure is 1.14% as calculated above, not 2.5%. The problem is that it is common for people to use relative pressure (eg 'lbs of boost'), which hides the fact that the absolute pressure is what should be used in any calculation.