What makes Test Course hard to catch up in can also make it challenging. I remember one race where I was QUITE underpowered but could keep up with the 3rd place guy as long as I drafted him. But the 1 and 2 cars were quite a ways ahead.
I gained 3rd place coming out of every 2nd turn, and lost it coming out of every second turn. But slowly, exhonorably, me and the AI I was duelling with managed to slingshot ourselves up to a point where I could JUST catch the trailing draft of the 2nd place guy (he was pretty small in the distance).
Then, I started to reel him in, climbing up his draft... With two laps left in the race, I slingshotted past him and picked up the front-running car's draft (again, barely). Once I got on HIS bumper, we traded back and forth for another 2 turns and then tried to whip past him coming out of the final turn towards the finish.
I miscalculated and nudged his back left bumper, and that bled off enough speed that I couldn't complete the pass. (I think I was still driving my 460HP RSI)
I came in a VERY close 2nd, but it was one of the most nail-biting races I've ever been in. Yes, and it was on the Test course.