The price has never been made public. It was a sweet deal though. He got paid for the car, still gets to drive it while someone else pays to maintain it. It's more dependable now because he has all the funding he needs to buy top notch components and he gets to keep his winnings. He's better off as the driver than he was as the owner.
He tested a new PTC converter down here right before he sold the car. It ran a couple 4.20's and a 4.19 to be the first stock suspension car in the 4 teens. It usually runs 4.20's and 4.30's depending on the track conditions. Out of the deal he also made the connection with the sheik who also put him in that Pro nitrous car in the video.