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Discussion Starter #1 (Edited)
I'm ready to make a (small) investment in video / data for DEs. I have an iPhone 8, GoPro Hero 3, and am looking at Harry's Lap Timer.

My goals:
Review video after DEs to see hands, placement on track, lines vs. cars ahead.
Overlay OBD data to see when on throttle and brakes and how hard.
Auto-timing of laps at established tracks. Not bench racing but to see if I'm making progress.
Share a lap or two with friends and family (non-drivers) so they can see what I'm spending my time and money on!

I'd love a seamless solution: app that turns on the GoPro, automatic overlay (but I can do that manually if everything is synced), automatic lap timing.

Please recommend which Harry's level and an OBD dongle. Hopefully the phone GPS is enough for starters.

Do I need to mount the phone on the windshield if I'm using the GoPro between the seats?

Is the iPhone video through Harry's a good start vs. a synced GoPro?

Thanks in advance,
Tom
 

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I have used HLT GrandPrix edition on a iPhone 7, with a Kiwi 3 BT OBD2, a SkyPro GPS XGPS160, and a GoPro Hero 5 black. I hang the iPhone from the window using a GoPro mount. I put the Kiwi through a 2nd cover plate that I have cut a hole in. I mount the Skypro and GoPro between the two seats.

HLT has been very stable, and getting better and better over the year that I have used it. It now shows braking as well as gas pedal position. I have not had any issues with the Skypro GPS. HLT sometimes reports an issue with the Kiwi but after a minute or so, the warning goes away and it always records properly. I can personally confirm that Harry, the author of HLT, is very responsive to emails.

I have had two problems, one minor with audio recording and one more serious with HLT sometimes not turning on the GoPro recording. This might have been my fault but I opted to address the issue by using the Iphone to record video and then uploading the GoPro video to replace the iPhone video. There is a youtube video where a person demonstrates this process. This takes a little effort to align the video timing but you get a much better picture with the GoPro than you do with the iPhone as there is much better video stabilization as the windshield mount shakes. I also find that the viewpoint of the GoPro shows my steering motion and position which is useful to have. As for the audio, I have hooked up an external microphone to the GoPro but the wind noise is hard to eliminate from the car sound, even trying to do this as a post processing step. I even routed the microphone all the way to near the exhaust but I still get a lot of wind noise.

Hope this helps.

Recently I had an issue with the club I was running with would not allow time recording so I opted to leave the iPhone in my glove box. Got most of the data but the acceleration plots were completely bogus since HLT uses the iPhone accelerometer. Need to find a better way to lock down the Iphone in the glove box.
 

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FWIW I have been using app based data and vid for 9 years. I started out with Race Chrono which was a very good early development app, and switched to HLT when I went with an iphone and RC did not support it at the time. It is available now though. My observations:

*All data loggers including Racepak, AiM, and other high end $2k plus systems have strengths and weaknesses. None are perfect and they all sometimes have dropouts, IT interface issues, and a bit of a learning curve.

* For the track day junkie looking to evaluate driving skills and improve performance, HLT GP is a pretty great bang for the $$. It will trigger multiple GoPro cams and will video from the phone itself. It allows you to do overlays within the phone with no editing software, and picture in a picture is possible although I have not done this. The learning curve is fairly quick with HLT and because you can get instant overlays that you can transfer to an ipad or larger screen easily, it proves to be a useful tool.

* For best corner data and positional accuracy, forget the internal iphone GPS and get a hi res GPS receiver. Position accuracy with the phone is around 30'. Position accuracy with a 5hz GPS receiver is around 3'. Both will give decent lap times due to the magic of interpolation within HLT but corner data with the iphone GPS is useless.

Race Chrono now supports iphone and there are several other apps that do similar things. I have the most time with Harry's and that is the one I both know the best and most often recommend. I have not used a dongle for car ECU interface but trust the compatibility guide at the HLT website. If they say it will work, it will. HLT does a good job with continuous support of users.

Here is a single cam vid with instant overlay from AAA Speedway while chasing a pair of 80s Carreras. They are 600lbs lighter with more tire but we still have fun together. Watch us drive around the 997 GT3 in turn 2 at 130 mph.
 

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FWIW I have been using app based data and vid for 9 years. I started out with Race Chrono which was a very good early development app, and switched to HLT when I went with an iphone and RC did not support it at the time. It is available now though. My observations:

*All data loggers including Racepak, AiM, and other high end $2k plus systems have strengths and weaknesses. None are perfect and they all sometimes have dropouts, IT interface issues, and a bit of a learning curve.

* For the track day junkie looking to evaluate driving skills and improve performance, HLT GP is a pretty great bang for the $$. It will trigger multiple GoPro cams and will video from the phone itself. It allows you to do overlays within the phone with no editing software, and picture in a picture is possible although I have not done this. The learning curve is fairly quick with HLT and because you can get instant overlays that you can transfer to an ipad or larger screen easily, it proves to be a useful tool.

* For best corner data and positional accuracy, forget the internal iphone GPS and get a hi res GPS receiver. Position accuracy with the phone is around 30'. Position accuracy with a 5hz GPS receiver is around 3'. Both will give decent lap times due to the magic of interpolation within HLT but corner data with the iphone GPS is useless.

Race Chrono now supports iphone and there are several other apps that do similar things. I have the most time with Harry's and that is the one I both know the best and most often recommend. I have not used a dongle for car ECU interface but trust the compatibility guide at the HLT website. If they say it will work, it will. HLT does a good job with continuous support of users.

Here is a single cam vid with instant overlay from AAA Speedway while chasing a pair of 80s Carreras. They are 600lbs lighter with more tire but we still have fun together. Watch us drive around the 997 GT3 in turn 2 at 130 mph.
Good info.
I've been using race chrono for about 5 years utilizing various android phones. When coupled with a Qstarz GPS receiver and common OBDii reader, I get a video and data overlay that gives me pretty much everything I need except oil pressure/temp.

The Qstarz is 10hz so it is pretty accurate with the speeds and location on the track. Having said that, 3' is about it for accuracy so figuring out if you're really hitting the apex is best left to a camera--preferably mounted tot he side of the car.

The data output can be setup numerous ways, with an overlay on a track layout showing speed, braking point, level of effort as well as throttle usage.

The typical 13mp camera on most androids are adequate for good 720dpi video. You can do the synching all on the phone or use something like racerender to put the whole product together just because you have more options for instrumentation layout.
 

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I use Harrys Grand Prix Edition, Kiwi OBD connector, and a bad elf GPS. When I shoot video which isn't all that frequently it runs a GoPro. I don't know about the newer GoPro's but some of the older ones will only write about a 15 minutes or so of video the SD card before they split the file, I understand the garmin's use a different file system (exFat or NTFS Can't recall) and don't have that limitation. Pairing the video with Harry's from the GoPro, if split, will require merging the files on a laptop then copying them over to the phone.

Lately I've been playing with some desktop software https://trackattack.io/ and using it to analyse my data from Harry's I find it easier to do this for track times on the desktop and this software works really well. I haven't tried their video overlay tech yet, but will see if I Can get to it this weekend and report back.
 

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I'm using Android and Track Addict (free) with OBD (I use the cheap $10 adapter), GoPro + Android HD 1080 video and Android GPS.

I using Race Render 3 for post-processing and multi-source data merge. I've also been able to export the data acquired by Track Addict for more intense analysis using Circuit Tools.

The biggest problem I have is the brake data is not accurate and the phone GPS data isn't accurate.

I believe brake data is an on/off guesstimate based on deceleration. I don't believe there is an OBD reading for brake pedal activation or pressure. I could be wrong.

The GPS is good enough for lap times and segment times, but does not provide good absolute position info. My next purchase is probably an off-board GPS.

I've been using my GoPro in-car with an adhesive mount on the plastic between the roll bars in my Boxster. The mount removes easily by applying a little heat with a hair dryer.

Next time out, I'm going to move the GoPro to the outside to look at my cornering in more detail.
 

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Discussion Starter #7
Thanks for all the suggestions.

I'm going to start with my iPhone 7 running HLT GP, Kiwi 3 OBD, and GoPro 3 on Lapis's lexan mount between the seats. I'll add an external 10hz GPS after the Dec. 1-2 DE.

Last few questions:

Should I run video from both HLT and the GoPro? Where should I mount my phone on the windshield - in my view or passenger side? Any benefit to put the GoPro somewhere else if HLT is capturing my perspective.

Thanks,
Tom
 

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Experiment with video and see which perspective you like. Dozens of possible options.

I mounted my phone with a Ram mount attached to the center of my dashboard so both driver and passenger (and rear mounted video) can see it. I used aircraft quality RTV and simply attached the ball mount to the top of dash. It is semi-permanent and good for about 18 Gs but will come off with a plastic scraper fairly easily to return it to stock. I want to see the HLT screen for instant feedback on predicted lap progress and improvements in cornering speed. It is a great learning tool mid lap and you know if you are on a flyer when everything goes green.
 

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Harry's added brake pressure in their latest release, I don't know if there's a channel in the cayman for it as I've not looked at it, I know a friends 997 has it. As far as Circuit Tools I tried that app and found Track Attack to be a lot easier to use, and produced the comparison charts that most interested me with less fuss. But they're both free to try so you should try them both out!
 

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Thanks for all the suggestions.

I'm going to start with my iPhone 7 running HLT GP, Kiwi 3 OBD, and GoPro 3 on Lapis's lexan mount between the seats. I'll add an external 10hz GPS after the Dec. 1-2 DE.

Last few questions:

Should I run video from both HLT and the GoPro? Where should I mount my phone on the windshield - in my view or passenger side? Any benefit to put the GoPro somewhere else if HLT is capturing my perspective.

Thanks,
Tom
You may know already but just to mention, LSR PCA wants all windshield mounted devices tethered to the car. to be honest I haven't seen them check lately. I use a CamKix wire tether for my Ram mounted AIM solo.
 

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You may know already but just to mention, LSR PCA wants all windshield mounted devices tethered to the car. to be honest I haven't seen them check lately. I use a CamKix wire tether for my Ram mounted AIM solo.
A few years ago we had some suction cup mounted cameras come loose and fly off in turn 1 at AAA speedway. A GT3 Cup car hit one going 150 mph and was not happy. A secure mounting solution is wise.
 

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You may know already but just to mention, LSR PCA wants all windshield mounted devices tethered to the car. to be honest I haven't seen them check lately. I use a CamKix wire tether for my Ram mounted AIM solo.
I use a RAM mount for my phone to the lower-right of the mirror. I put a stick-on GoPro tether on the back of my phone and slip the loop over my mirror. I also use a stick-on tether for my GoPro mounted between the seats. Here is an example of the viewpoints the two cameras give me: https://www.youtube.com/watch?v=kzSGTdsByik
 

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Has anyone had a chance to verify HLT support for brake pressure in the 981/991?
I used HLT in April at MSR... it has "quasi" brake pressure in the overlay, but it is only "interpreted" using negative G. Haven't found the custom PID for brake pressure on 981 CAN bus -- I don't think anyone has at this point ???
 
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