[narudnad]

Thank you for sharing OP! Good stuff 👍

[M4ROLLIN20]

Originally Posted by BackOnBlack

Thank you!

The setup is very simple: I purchased the ODB reader (https://www.getbmwparts.com/oem-part...-61432450841), installed the M Performance Analyzer app on my iPhone 14 Max, and that's it.

The app connects to the ODB connector via Bluetooth, you enter your VIN into the app, select the car model from the app database, and that's it. I position the phone with a two-suction mount behind the passenger seat, hit record, and it records when the car moves, and stops recording when the car is turned off automatically.

For the price, it is good value. But, it does not record lap times or any data other than what you see on the screen. It is not customizable in terms of graphics. When the session is done, I export the video, which it stores in Photos, then I transfer to my Mac for editing.

If you are after detail data analytics, this is not the right solution. I'd prefer to go the AIM or VBOX route for that. But for my beginner purposes, this is sufficient for now.

Absolutely amazing, what a knowledgeable and intelligent young man. Good for you. Thank you for all the information posted.

[BackOnBlack]

Originally Posted by M4ROLLIN20

Absolutely amazing, what a knowledgeable and intelligent young man. Good for you. Thank you for all the information posted.

Thank you!

I am very young at heart and try to enjoy my toys, but I am past my mid-life

[BackOnBlack]

To update this thread on what I think really happened and the lesson re-learned about i the 'tank slapper:'

Originally Posted by BackOnBlack

... Eventually, I started my second run, and through one of the critical turns, I saw the racing line was dry, squeezed the throttle after the apex, and had a scary tank slapper at about 60-65 mph, which luckily I was able to catch and stay on track.

My next track day is in a couple of weeks, so I got few things ready for it and the last item on my to-do list was to have the alignment checked. Besides the tank slapper I mention in this thread during a left hander, I also experienced a low-speed oversteer during the autox, which was again during a left-hander. The two incidents just kept bugging me. Better safe-than-sorry: I wanted to have the alignment checked, even though the car tracks fines, steering wheel is straight, etc.

It turns out that the rear right side had moderate toe-out and left rear side had significant toe-in. This misalignment, in addition to, cold under-pressure tires, must have caused the tank slapper.

So, don't trust the factory alignment before going to the track or even autox, just have it aligned. Additional note: Have the steering recalibrated after alignment, which is part of the new electric steering SOP apparently