downloaded an iphone app called Harrys Lap Timer and ran it on Sunday. For $6, it's actually pretty cool...

I did some testing on Saturday while working at Exotics. I had it mounted in our ride vehicle which was a Hummer H2... which is pretty cool seeing a hummer H2 hit nearly 0.90 lateral G's . I would recommend playing with the app a day or two before a track day so you can figure out how it works.

The phone needs some basic calibration to get things working. It has to be mounted as upright as possible... I bought a windshield mount from bestbuy to aide in this.

It'll give you a real time account of your current lap, as well as either your best lap or the previous lap. You can switch to a see an active g-meter, and it'll still track your laps. You can also do intervals as well.

The data provided is pretty awesome too, some of which is displayed below. Anyways, to screenshots:



Some data and screen shots:
S2000 best lap: 2:45.24
S2000 highest mph: 106.4 mph (just before turn 3)

Civic best lap: 2:51.08
S2000 highest mph: 95.3 mph (just before turn 3)

Civic data:

This shows where I'm braking and accelerating, including speeds. The braking points are slightly off due to the sensitivity of the app registering me braking when the car is struggling to accelerate (ie. turn 2, turn 3)

S2000 data:

Speed differences are pretty incredible to see...

G forces generated at specific points on track






Overall:
Pros
- Inexpensive
- plenty of data to comb through
- real time view of g-forces, as well as lap times
- provides graphical and textual data
- Export options!
- has a lot of track maps for free downloads.

Cons
- irritating at first to use... no initial directions on how to set up.
- removing the phone and starting the application sometimes forces you to recalibrate
- minor hiccups in the data acquisition

I still haven't gone thru ALL of the features... but would highly recommend it to any other track monkeys.

 

nice. this plus Dynolicious = budget win

and an Ipod Touch, no Iphone...

 

I've done alot of testing on Harry's Lap Timer with the GPS timer feature, but not any at all with the accelerometer features. Once I figured out how to set the POI's (lap triggers) it has been a great little gadget for track days.

I recently used some gift certs to buy the TomTom iPhone car kit that works with Harry's Lap Timer and tried it out:

TomTom/Harry's PROS:

1. The most solid and versatile mounting kit for the phone I've seen, and it includes a charger
2. Lap timing was consistently within .025 second of the RFID transponder, and it never missed a single lap (it occasionally would miss with the built-in GPS)
3. If you dont want the phone, it now works with iPod Touch models, meaning you can get a pretty cheap GPS timing setup. (see tomtom site for specific models it works with)

TomTom/Harry's CONS:

1. Comes with just the hardware unit with mount/charger/gps. You must pay more to downlaod the maps/directions software. I really just wanted it for timing, so I havent even bothered with the actual maps/directions aspect, but I've heard its top-notch.
2. Speakerphone feature picks up too much noise from any but the quietest of vehicles. Its unusable for most cars.

 

a few guys have dynolicious and say it's pretty basic for the cost (in comparison). Seems it's more geared towards drag racers, since the G-meter aspect is in Harry's.

BUT, I haven't had a chance to try it out myself.

 

ya, but it is like 12 bucks and from what I have read is pretty accurate/consistent. so like.. why the hell not just to play with.

 

Used the application as well, but had problems with it, as it didnt record properly.
Guess I need to lock at it a bit deeper....

 

This is interesting. Is it designed only for the iPhone 4?

I'm asking because the iPhone 4 has a gyroscope that iPhone 3GS and iPod Touch will not have. He could do a lot more neat things by balancing the compass and gyroscope against each other to generate calculations.

Event organisers didn't have an issue with an iPhone on a windscreen mount?

 

The app details say it's for iphone 3gs iphone4... maybe even the touch, but I didn't pay that much attention.

It was a HPDE with Porsche Club. Porsche club are generally pretty strict about things (they didn't let anyone have an exterior mounted camera)... but they let the mount pass. The mount is pretty sturdy, albeit still a windshield mount. The clamping force on the phone for the mount is pretty impressive too...to release the clamps, there's a button on the back that unlocks the "ratchets".

I'm sure a hard mount option could be done where it would pass race tech.

 

Thanks for the review, I have been considering this for my 3G, but it is so slow since 4.0, I am worried that it will not work smooth.

Also do you work at Exotics racing? I was just there a month ago in Vegas, I did 5 laps in the F430 Scuderia, it was a blast!!! I am going out there again for my job, I want to do the R8 next time.

 

Do you have to download track layouts? Or does it record a "line" via gps?

It would be cool to have something like this for solo days.

 

I got so sick of my 3G that I ended up selling it to radioshack for $107 and got a iphone4. SOOO much better than the crapfest that is 4.0 software on the 3g.

Yep. If you had the GoPro on the driver's window, then I was working that day, but in the Gallardo LP560-4.

We now have a Murcielago LP640-4. It's a beast to drive though... very very difficult.

You can download OR just let it record. The system doesn't have LVMS and I attached it to our ride car (above-mentioned hummer) and it drew the map out for me.

 

That's very interesting. I cannot imagine how he'd have programmed it without the gyroscope...but I'm also not very clever.

Perhaps it doesn't do everything with the 3GS that it does with the iPhone 4.

 

All the iphones and ipod touches have some form of gyro/accelerometer built in dont they? I think I remember reading the iPhone 4 is supposed to have an improved gyro in some way.

The main difference that makes the app recommended for the 3GS and 4 is that its main feature is the use of built-in GPS in those phones.

 

Well...you can obviously use any GPS chip to get speeds and times.

What's puzzling me is how to read G's without the gyroscope in the iPhone 4.

Fascinating and a great application, however the hell he did it. :-)

 

AFAIK, all ipod touches and iphones have some sort of gyro. not all have GPS however. i think thats how it is.

 

http://www.youtube.com/watch?v=VP4-wdMMLFo

There's a lot of information that seems to say that there was no gyroscope before the iPhone 4.

http://news.cnet.com/1606-2_3-50088644.html <--In Steve's words (video at top). He physically shows how the gyroscope is better than the accelerometer-alone setup in the previous iPhones.

http://www.youtube.com/watch?v=ORcu-c-qnjg&hd=1

The ability to measure gravity, pitch, roll and yaw, in addition to basic acceleration, is new to the iPhone 4.

 

ah, yes, i was thinking of the accelerometer, which previous models do have. it pretty much does the same thing, maybe not as accurate though. can still sense gforces and orientation.

 

http://www.gps-laptimer.de/ That is the developer's Web site.

 

Anyone have experience with Android phone lap timer apps?

 

The accelerometer in the 3G is mediocre at best. I wouldn't trust this app much unless it's being used with an IP4.

Quote from a website:

The iPhone 4 adds another sensor: a three-axis gyroscope. When combining the gyroscope with the accelerometer, this gives the iPhone 4 six axes on which the it can operate. This is designed to make the iPhone 4 more sensitive, responsive, and powerful for gaming.

 

If you're referring to trackmaster, yes. It works very well. Compared with AMB transponder times it was within .100 - .050 a second on lap time and that was a very "foresty" track known as Pacific Raceways near Seattle. As Spokane Raceway Park where there are no tree it was typically identical in accuracy as AMB. The Theoretical lap time is a great feature as well along with sector times, throttle/coast/braking data and google-earth overlays. Not bad for and APP under $7.

 

Yep, that's the one i'm referring to. I'll give it a try at my next event.