Full disclosure, I didn't do a lap.
But, the reason I didn't do a lap is the same reason I am 99% sure it doesnt count towards the profile TT information: there were no in-game credits for gold/silver/bronze since there were no aforementioned medals associated. From what I understand, you either get in the top four or you don't. There's nothing that states if you get within 3% of P1 you get anything at all.
The 911 RSR at Tona RC interests me, but these other two don't so I doubt I'll even bother for the reason(s) above.
I was under the impression it was just for the livery. If you actually get the car, I will be bummed as that in itself would've been worth 3.5 minutes of time! I can't imagine PD giving away this 18mil car for just doing a lap, and it would be ridiculously unfair to all those outside the US who couldn't compete. I wouldn't get my hopes up for the car, but if you get it more power to you!
"This is an Online Time Trial hosted by Porsche for 3 consecutive weeks. If you make it to the top 4 in each of the challenges, you will be invited to the Final Event which will be hosted live.
You will also receive an iconic car livery of Porsche by just entering the events!"
Gran Turismo Official Website
www.gran-turismo.com