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Which value to trust?? HPTuner

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Old Oct 28, 2019 | 08:20 PM
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Default Which value to trust?? HPTuner

This is a common occurrence, I was wondering if someone knew which is the correct value, which one to trust:



I'm getting two different KPA Readings from my HPTuners app..

Thanks,
Andy
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Old Oct 29, 2019 | 07:45 AM
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Which OS are you running? IIRC, Certian ones you have to use the the stock MAP sensor and others you have to use the upgraded MAP, 2 bar, 3 bar.

Which MAP reading is right KOEO?

I'm guessing the stock MAP tops out at 105kpa and that's it?
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Old Oct 29, 2019 | 08:01 AM
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Originally Posted by LilJayV10
Which OS are you running? IIRC, Certian ones you have to use the the stock MAP sensor and others you have to use the upgraded MAP, 2 bar, 3 bar.

Which MAP reading is right KOEO?

I'm guessing the stock MAP tops out at 105kpa and that's it?
Hi Jay,

Thanks for chiming in! I'm using a 3 bar OS.
With KOEO, both sensors are correct. The indiscrepancies start at higher RPM ranges like 4500+ from what I've noticed.

That is correct, the stock map tops at 105.

Any ideas?

Thanks,
Andy
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Old Oct 29, 2019 | 08:06 AM
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What sensor is the graph kpa reading from?
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Old Oct 29, 2019 | 08:08 AM
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Funny timing on your post, I literally just realized after I responded here, that I'm still referring to the 1 bar MAP Sensor in the graphing, vs switching to 3 bar.

I just switched it to the 3 bar, I will do a test run and report in.

Interestingly enough, things got confusing because the silly Stock graph map goes above 105, yet the channel itself tops out at 105, throwing me for a spin before realizing it...

Thank you both!
Andy
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Old Oct 29, 2019 | 11:58 PM
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Andy,

you need to put the 3 bar map in the channel list. And delete the 1 bar.
Of course you will need to update the layout to read the 3bar as well.

BTW, the 3bar OS won’t give you a map reading Key On Engine Off. You have to crank it first. Best to unplug the injectors so it doesn’t start. Should show near 100kpa depending on the current barometer.

Ron
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Old Oct 30, 2019 | 10:00 AM
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Originally Posted by RonSSNova
Andy,

you need to put the 3 bar map in the channel list. And delete the 1 bar.
Of course you will need to update the layout to read the 3bar as well.

BTW, the 3bar OS won’t give you a map reading Key On Engine Off. You have to crank it first. Best to unplug the injectors so it doesn’t start. Should show near 100kpa depending on the current barometer.

Ron
Hi Ron,

Thanks for chiming in.

I will remove the 1 bar from the channel list - maybe it's throwing something off.
I updated all the layouts to 3 bar map last night, and did some test hits. Unfortunately, there is still a discrepency between what's displayed on my channels, vs what's displayed in my graphs below.

I'm going to guess that this is normal though - the theory here is that the channel list doesn't have the same refresh rate that the graph does, and this would make sense. For example, my RPM in the graph might say something like 6357 RPM, my channel list will say 6320. Etc.

Thanks,
Andy

P.S.

didn't realize 3 bar os did that (KOEO reading) I'll have to keep that in mind. You probably saved me trouble in the future - I can just see myself scratching my head. Not any more. Thanks!
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Old Oct 30, 2019 | 10:02 AM
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But I will say though, for anyone who might read this: Do not forget like I did, to update the layouts with the proper map sensor. Obviously once I did this, I'm now accurately tuning, vs confusing it with the 1 bar map readings which were obviously being pushed past their MAP reading capability...but some how still going up to the 120's and 130's even 140's in some cases.

Thanks!
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Old Oct 31, 2019 | 01:35 PM
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Originally Posted by AndyTA
Hi Ron,
Unfortunately, there is still a discrepency between what's displayed on my channels, vs what's displayed in my graphs below.
I'm going to guess that this is normal though - the theory here is that the channel list doesn't have the same refresh rate that the graph does, and this would make sense. For example, my RPM in the graph might say something like 6357 RPM, my channel list will say 6320. Etc.
That isn't enough discrepancy to worry about.
however. do enough logs, you will often see huge discrepancies. Like the map reading heading to 0 before you take your foot off the gas.
I mentioned this on the hpt forum with basically a "that's normal" response. I call BS. The charts and graphs just don't respond correctly at times...….

Ron
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