FergusH

Ok, I realize that this isn't a common combo but hopefully someone's tried it:

I'm trying to use a Vbox Sport with Porsche's Track Precision app. In this mode, the Vbox will be the GPS for Track Precision, instead of the phone.

I've also got XGPS160 external GPS and when I use that with Track Precision, TP's GPS screen changes from showing "Smartphone GPS" to "Dual XGPS".

However, when I use the Vbox, TP still says "Smartphone GPS" so I can't tell whether the phone's internal GPS is being used or if the Vbox's GPS is being used.

Any suggestions? There's no information about this in the TP manual or the FAQ.

Thanks.

Update: I found out that this is a known issue with Track Precision that will be fixed in the future. The good news is that the Vbox Sport, when connected to the phone, is definitely being used by the app for position data.

DrCGuerra

I do not have an answer to your question but wanted to know which you preferred, the VBOX Sport or the DUAL XGPS 160 (SKY PRO)? I am looking at buying one and using Harry's Laptimer with it. If you prefer the VBOX, did you use it with the external antenna? On Harry's website, they commented that the internal antenna is not on par with the unit and recommended using it with the external antenna. Thanks

FergusH

I would probably go with the XGPS. I don't have extensive experience with using the Vbox Sport just as a GPS for HLT but I think it would be overkill for that purpose.

What it is useful for is a backup to another lap timer. As you probably know, the Vbox Sport is also a data logger. You just turn it on and start driving and it'll record everything until you stop the car. The log files are stored on SD card and can be analyzed using Vbox's Circuit Tools

Tomorrow I'm going to be doing some testing with the Porsche app but I'll probably also get the chance to compare the two GPS units for accuracy. So far, my gut feeling is that they are about the same. I'm not using an external antenna for the Vbox, which would probably make a difference.

ProCoach

I have never used an external antenna with multiple VBOX Sport units. High quality, low hassle.

DrCGuerra

Let me know how it goes and which gave you the most useful and user friendly data. Thanks for your reply.

FergusH

Well, that was interesting:

I did some testing today and it turns out that the Vbox Sport is considerably more accurate than the XGPS160.

I did several tests but the simplest was using the Vbox Sport with Track Precision, driving a defined track, then driving the same track but using the XGPS as the data source.

XGPS160:



VBox Sport:



I'm going to play with this some more, to make sure I'm not missing anything but I think my default GPS is going to be the Vbox Sport. It has the added benefit of being a standalone logging device.

ProCoach

Why does this NOT surprise me?

I do stock them. And for $429 plus the mount, it's a good deal for the 20Hz quality. MoTeC is three times that for their RaceGrade and doesn't even include a logger!

DrCGuerra

Thanks for keeping me in the loop. I am guessing you used Porsche's Track Precision? It doesn't get very good reviews. Have you tried it with Harry's Laptimer?

FergusH

Track Precision definitely does have its drawbacks but I'm very confident that Porsche is going to get them resolved. When it works (and it's now working for me 99% of the time), it's simpler than Harry's Laptimer and provides more data from the car.

I've tried the Vbox Sport with Harry's Laptimer and it seems to work fine. I haven't done any tests to see if I get the same results as with Porsche TP but I believe they'd be the same (i.e., the Vbox is more accurate).

I just finished taking a look at some other data I already had and the Vbox definitely seems more accurate:




Blue is data from the Vbox directly (i.e., analyzing the log file directly from the SD card in the Vbox); red is data from the XGPS via Track Precision. The Vbox starts logging as soon as you start moving, so the blue track includes me coming on and off the course, while the red track doesn't have this. Also, I did a separate test to make sure Porsche's app isn't doing something bad when it exports the data as a .vbo (Circuit Tools) file; it's not, so the difference you're seeing should be just from the logging devices. It's a big difference!

DrCGuerra

Wow. It's amazing how tight the blue lines are & how spread out the red lines are. It makes me believe the XGPS is useless for track data. I'm getting the VBOX Sport. Thanks for sharing.

MarcD147

I have been giving feedback to Porsche and someone reached out and asked for feedback and my data.

there is an update coming to the app in march and maybe more later.

some issues are in the app but some issues are caused by confusing or lack of help/documentation (there is a good thread in the GT4 forum with howto videos)

btw I use a vbox as an external GPS to the phone (and have the external antenna for the vbox; haven't tried yet without it)

DrCGuerra

Is it easy enough to try with and without it and are you willing to try and share your results and thoughts? I am not sure I want to install the external antenna. Thanks

ProCoach

If the VBOX Sport is mounted on the inside of the windscreen with a clear view of the horizon forward of the car and unhindered view of the sky above through the glass, no external antenna is necessary.

I have used the VBOX Sport since its release (my demo unit as a larger Racelogic dealer) and have extensive experience with this device.

DrCGuerra

Thanks for the information.

ProCoach

I appreciate FergusH's posting of the GPS paths. That is cool!