I was driving on the main route between Phoenix, and LA today on my way so see family for the weekend. Stopped at the first rest stop on the CA side. I pull up, and there is a stock looking (wheels etc) 2013 GT parked on the end away from all other cars. I park a couple of places away. When I get back to my car, I still don't see anyone that might be the owner. As i pull out of the parking spot I see a guy walking up that silver GT. I get on the Freeway, and he gets on right behind me. Trails me for a few miles a couple hundred feet behind me. Traffic is very light, we are in the middle of the desert on a week day. He eventually pulls up to me in the left lane. We acknowlege each other then I hit it in drive at about 70. I have a 2012 A6 premium, so my car jumps out, I notice he has to down shift, (M6) so my momentum had him up to about 120-130 by about a half car. I then shut down. He had exhaust for sure not sure what else. I am bone stock. I let him go ahead for about 20 miles, then roll up to his left again. This time I let him down shift before hitting it. We both hit at 70 again, then he gets the jump by about a car up to 120-130. We slow down roll down the widows. He asks me if I have a tune, and I say "no bone stock". We give each other a thumbs up, and proceed on our way to LA. That was just good clean fun for a few mins on a 5 hour drive. Guy was cool too!