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Old 04-09-2013, 03:53 PM   #221
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With 2.7, hydra added the units in with the data. I just strip the units (remove vacuum) and have made a custom xml entry for the column names. Works fine for me.
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Old 04-10-2013, 01:10 PM   #222
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why would they do that ... that screws the users and is a pretty crappy way of storing data.
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Old 04-10-2013, 01:13 PM   #223
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Who uses a Hydra?
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Old 04-10-2013, 01:24 PM   #224
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why would they do that ... that screws the users
Sounds pretty in line with the hydra business strategy.
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Old 04-12-2013, 06:50 PM   #225
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yeah the 2.7 has non-numeric data; the unit of measure in every column.
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Old 04-13-2013, 04:21 PM   #226
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it may mean that I stop supporting Hydra after 2.6 ... unless I really feel like trimming that garbage out. Someone needs to start a thread in a place they look at.
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Old 04-13-2013, 08:28 PM   #227
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we don't visit hell often.
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Old 04-15-2013, 05:53 PM   #228
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hahaha ... I like your style Braineack!! My sense of dry sarcasm!
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Old 04-20-2013, 04:53 PM   #229
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it may mean that I stop supporting Hydra after 2.6 ... unless I really feel like trimming that garbage out. Someone needs to start a thread in a place they look at.
Thanks and DONE. I guess im just a glutton for punishment.
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Old 04-23-2013, 09:04 PM   #230
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Keep me posted on the outcomes of it ... I am concerned when loggers start doing this crap. Its non-standard ... beginner programming design to do logs like that. Thats how I honestly feel.
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Old 06-11-2013, 09:58 AM   #231
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I've just started using VD for tuning and absolutely love it. But of course there is always one more little feature request!

In order to be able to compare apples to apples, I would like to eliminate the influence of intake air temperature on the result. I can already kind of do that by switching VD into SAE mode and entering the average IAT during the run, but if possible I would like even better comparability. My IATs change considerably during a run because of the tiny little intercooler. So a mode where every data-point gets corrected for IAT would be totally awesome!
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Old 06-11-2013, 11:22 AM   #232
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I'd like to be able to graph the extra things. Boost and AFR never shows up in the graphs correctly and I can only plot other the data on another chart that I cant export with the TQ/HP plot. We should be able to select those things to put on the main power plot, more like the winpep7 software.
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Old 09-19-2013, 05:00 PM   #233
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Default Using VD's SAE Correction Correctly

The point of the SAE correction is to correct the output for current temperature and pressure conditions so they can be compared (imperfect, but much better than nothing). The problem is that the pressure input requested by VD is “Barometer.” Barometer readings reported by the weather service are not straight pressure readings. Rather, they are pressure readings corrected to Sea Level. This is done because aicraft altimeters work in this fashion and it also allows meteorologists to directly compare a barometer reading from, say, Colorado to one from Louisiana to identify low and high pressure areas. Wikipedia has a brief description of barometer compensations here: Barometer - Wikipedia, the free encyclopedia. Altitude-based correction tables are here: http://www.novalynx.com/manuals/bp-e...ion-tables.pdf.

Here’s a worked example from the other day. I did several runs near Granbury, TX (elevation ~900’). I wanted to SAE correct these so that I could compare them later. Getting the current observation on my smartphone showed a temperature of 92°F and barometer of 30.02”Hg. To get actual pressure, I go into the tables and look up the elevation correction for 900' (0.96”Hg). Subtracting the correction from the reported barometer reading, I get 29.06”Hg as the actual pressure. I plug 92°F and 29.06”Hg into VD to get an accurate SAE correction.

This should help you guys in NM and CO.

Hopefully, VD will have an "Elevation" or "Altitude" input for the SAE correction soon.
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Old 09-19-2013, 05:04 PM   #234
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Quote:
Originally Posted by hornetball View Post
The point of the SAE correction is to correct the output for current temperature and pressure conditions so they can be compared (imperfect, but much better than nothing). The problem is that the pressure input requested by VD is “Barometer.” Barometer readings reported by the weather service are not straight pressure readings. Rather, they are pressure readings corrected to Sea Level. This is done because aicraft altimeters work in this fashion and it also allows meteorologists to directly compare a barometer reading from, say, Colorado to one from Louisiana to identify low and high pressure areas. Wikipedia has a brief description of barometer compensations here: Barometer - Wikipedia, the free encyclopedia. Altitude-based correction tables are here: http://www.novalynx.com/manuals/bp-e...ion-tables.pdf.

Here’s a worked example from the other day. I did several runs near Granbury, TX (elevation ~900’). I wanted to SAE correct these so that I could compare them later. Getting the current observation on my smartphone showed a temperature of 92°F and barometer of 30.02”Hg. To get actual pressure, I go into the tables and look up the elevation correction for 900' (0.96”Hg). Subtracting the correction from the reported barometer reading, I get 29.06”Hg as the actual pressure. I plug 92°F and 29.06”Hg into VD to get an accurate SAE correction.

This should help you guys in NM and CO.

Hopefully, VD will have an "Elevation" or "Altitude" input for the SAE correction soon.
Do remember that the barometric pressure correction for SAE doesnt really work correctly on turbo cars. This is why FM's dyno numbers in colorado always seem inflated.
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Old 09-19-2013, 05:09 PM   #235
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Good point. All I'm trying to do is compare runs taken a couple of months apart. Nothing's perfect.
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Old 09-19-2013, 06:00 PM   #236
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Quote:
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Do remember that the barometric pressure correction for SAE doesnt really work correctly on turbo cars. This is why FM's dyno numbers in colorado always seem inflated.
It doesn't work on turbo cars that use EBC that corrects to the same absolute manifold pressure regardless of altitude. If you run a turbo car at sea level and 5000' with the same PSIg levels, SAE corrections will get you within 2% (which is as good as it ever gets with a dyno).
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Old 09-19-2013, 06:08 PM   #237
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So . . .

EBC = Absolute Pressure Controlled (SAE Pressure Correction Not Applicable)

Wastegate Only = Gauge Pressure Controlled (SAE Pressure Correction quasi-Applicable)

But what about temperature. With an intercooler, it seems like this turns into a mess because the intercooler works so much better when it cools off. This is really my dilemna much more than pressure. How to compare a run made in August to a run made in October. Maybe it can't really be done?
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Old 10-22-2013, 12:46 AM   #238
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Love this program!

Here's a couple minor issues/annoyances I've ran into so far. Maybe we can get a fix or maybe someone else knows?

First, is the way boost is displayed at the bottom of the plot. There's an option to not change the units, convert to psi, etc., but none of them work out very well for me.

Pic 1. If left to "no change" it displays kPa, but goes crazy drawing a bunch of gray / minor axis lines... just really clutters it up and doesnt actually help you read the chart.

Pic 2. Convert to psi- doesn't scale the Y axis right and does not display a scale.

Pic 3. kPa displayed fine again, but again the scale isn't quite right... now it only shows every 100 Kpa.







I see that you can zoom in/out, etc, but either way it seems to me like it's not auto formatting it quite right. On other platforms/tuning tools it seemed to work perfect. If I'm missing something, please correct me!

Other issue I ran into was loading a Megalog viewer-cropped file into the program. I had a super long datalog with a pull in it, so I cropped it out using the megalog feature to "remove all data before this point" and "remove all data after this point", etc and saved a copy. Vdyno would not take it. I tried manually editing out the rows of the original datalog, saving a copy, and Vdyno took it just fine.
Attached Thumbnails
Virtual Dyno-nochange_zps40402ba7.jpg   Virtual Dyno-psi_zpsb649174c.jpg   Virtual Dyno-millibar_zps4aaea6bb.jpg  
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Old 10-22-2013, 12:54 PM   #239
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1. If I want to plot boost in psi, I always insert my own PSI column into the log using Excel. If you know your static pressure (you can get this from the log if you grab your MAP with the engine not turning) then the formula is:

Boost (PSI) = 14.7 * (MAP - Static P) / Static P

If you don't know your static pressure and are near Sea Level, just use 101.2. Should be close enough.

2. Magalog Viewer probably stripped the column names from the file. VD needs these.
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Old 10-22-2013, 02:02 PM   #240
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I took a look at the stripped file... Only thing I noticed missing was the firmware info at the top. All of the columns and labels were still there. I submitted the error, maybe something will come of it.

I will give the psi column creation a go. I guess it's not too much work... I don't do the vdynos all that often.
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