Originally Posted by von_zoom
Seems to be getting a little more imvolved than downloading the program. Now, as I understand it, in addition to the program, the mount, and the iphone 4S, I will need (or simular to) a Emprum Ult. GPS unit, and a PLX KIWI device. The $9.00 app (or is the Pro recommended instead) has suddenly gone to $260.00 plus/minus. Am I correct?
I'm slow, but getting there. Thanks for the input.
You are correct. I'd suggest the pro version, worth the difference.
The external GPS (like Emprum UltiMate) is recommended for increasing accuracy and refresh speed. This is ~$100
The KIWI OBD2 is recommended for capturing throttle/brake data. This is ~$150.
In my opinion, the external GPS is much more important than OBD2 data. I'd rather know my speed through corners in different laps more accurately than what was the throttle position. Since the speed changes are recorded with (I think...) GPS data, you see where you braked, and where you started accelerating anyways.
You can analyze your lap data in many ways: directly in iPhone, in iPad (you have to buy the iPad app) or on you PC for example with ChaseCam. It can compare laps, so you can see what have you done better in your fastest lap. Again, if you braked earlier/later in a given lap compared to your fastest lap, it is very easy to see. I attached some iPhone screen shots below.
The red one is the fastest lap. These are showing speed (not speedo but GPS speed) and as you can see, you know where you braked etc. You just don't know what is the brake pedal position (and you may not know this even with KIWI, because it is up to the car which data it transmits). You can also see things like lateral/lineal Gs, elevation change etc.
The whole track:
Zoomed-in to Turn 2:
Zoomed-in to Turns 5a-5b-6. You can see differences of taking different lines: