terrible traction problem

So I went to New England Dragway last night for my first time ever on a track, and it was a lot of fun but also very frustrating.

My first two runs were fairly respectable -- 14.23 @ 100.5 w/ 2.47 60 ft on the first, and 13.90 @ 99.77 w/ 2.19 60 ft on the second . . . . I was happy to have broken into the 13's right away and was looking forward to improving as the night went on.

Then on the third run, it changed drastically . . . I spun the tires badly, major wheel hop and everything, spun again when hitting second, terrible 60 ft and 16.4 elapsed time. On the next two I tried to go easier off the launch and improved it slightly (15's) but then it just kept getting worse. At the same time several other cars were having traction problems; it was a humid day and it had just cooled off so we thought the track got damp with dew or something.

I was going around the water, and doing a very small burnout (no brakes) as I had read on the forums. I took a couple breaks and I could see that there was crap all over my tires, sort of a mixture of greasy melted rubber and road grit. I should have stopped to think this through, but it being my first time and with all the excitement and frustration I didn't really put 2 and 2 together. I figured the small burnout should get that stuff off of there ; and I had read that you should not do a real burnout on street tires. Plus I was nervous about trying a real burnout since my car is a stick and I've never practiced it off the track.

Now I realize, I needed to get that crap off the tires. That was the problem for sure ; until I got that stuff off of there, I was doomed. Now I'm thinking maybe I should take some king of metal rasp or something to scrape that stuff off between runs ; or try a real burnout to get it off.

BTW -- tires are Nitto 555 275/18-40's ; I started with the tire pressure at my normal 32 psi and then later dropped it to about 24, this seemed to help maybe a little but could not overcome that greasy mess on the tires.

So now I want to go again sometime, but not until I have this problem figured out.