VBOX vs XGPS160 for a good setup?

[bleunetizen]

Hi Harry,

I've been reading quite a few things about the LapTimer app from your website and here in the forum but I wasn't sure which accessories I should purchase.. a few questions below

1. Your website suggests NOT to use any other bluetooth devices while it is running in 20hz mode, does it mean I need to buy a WIFI OBD2 tool?

2. In real life, how much difference does it make between 10hz and 20hz, in short, is extra money spent on VBOX worth it or is XGPS160 good enough for most people? Does it mean simply mean it is only accurate up to 0.1sec vs 0.05sec?

3. All the video's on your youtube channel seems slightly out of sync between the video and the OBD data (rpm, accel), it seems like the video is always about 0.5sec slower, is this happening because it is recording from GoPro or is it the case all the time?

4. Is iPhone4 powerful enough to do 20hz logging, video recording (gopro and/or phone camera) and OBD recording without problems?

5. Other than 20hz support, is there any other features that are only in the Grand Prix edition?


Thanks

Chad

[Harry]

Hi Chad,

1. Not necessarily. The VBOX 20Hz plus a OBD BT1 has been used successful often although the devices use up most of the available bandwidth. In general it is good to have some buffer to fight disturbances from other devices. In case you run into problems, LapTimer allows slowing down the VBOX to 10 Hz (which is enough).
2. I'd suggest to go for the VBOX if 20 Hz is important for you and only if you add an external antenna. In case you are not sure, 10 Hz will be enough the XGPS will give you better value for money.
3. That can be adjusted / tuned - search for "sensor delay" here on the forum. Due to the different sensor timings and configuration it is not possible to have one setting that is always right.
4. No. It will work with an external GPS only (10 or 20 Hz). OBD is extremely sensible to system load as the fix times cannot be reproduced (like GPS) and lags occurring cannot be compensated. In general, I do not recommend to use the 4 any more, it will go out if service with iOS8 too.
5. Please check http://www.gps-laptimer.de/LapTimer_Products.html; it has a lot more analytic functions plus MultiCam support including reference lap video comparison

- Harry

[bleunetizen]

Thanks for the prompt response

Regarding vbox and 20hz, are you suggesting that without the external antenna the 20hz won't be as accurate?

I also have Galaxy Note 3 which is much faster than my iPhone4... but it looks like iPhones are more popular here and only the iPhones get GrandPrix edition with 20hz support and other features.. is this coming to Android anytime soon?

Thanks,

Chad

[Harry]

Android Pertolhead supports the 20 Hz mode for VBOX too. This will change once GrandPrix becomes available, but there will be an upgrade available. 20 Hz does not contribute a lot to timing accuracy, position accuracy is the critical item. While the VBOX delivers great accuracy and rate with an external antenna, I found it pretty weak when using the internal antenna.

Harry

[bleunetizen]

Thanks Harry,

Just purchased and downloaded the android version, and ordered XGPS160 and OBD2 reader.. look forward to my track day next week