I still think you could do that today, take a 9.50 car and run 9.90's without any throttle stop and actually be competitive. Anything much quicker than that, may be a little more difficult because the amount of momentum it would have. A few years ago I borrowed a car and it ended up having a bad fuel pump. The car normally ran 5.70's but kept running out of steam because of the pump and would only run a high 5.90. So I just dialed a 6.20 and peddled the last couple hundred feet. It was a big money bracket race, but we still ended up going 8 rounds that night. I actually thought it was some of the most fun I had racing ever. Even today, I will usually dial my car 3 to 5 hundredths slow, and peddle it.