Apparently I suck at drag racing...

I have a timing slip from 1966...18.18 @ 73.41 mph.

'61 Impala ragtop with a 283/3 speed/ 3.70 gears. Around 4200 lbs.

You're doing ok...
That is really cool.... from 1966 :)
I still have my 1st time slip too. It was in a 150 dollar 1973 Dart Swinger. High mileage, with a slight miss (probably bad valve). 318 2bbl, single exhaust, auto, 2.76 gears. 16.72 @ 81 mph