Hmm my VX has a wobbly carb and doesn't perform well until it's warmed up. Maybe I should check the carb mount too...

Easiest comparison is draw three lines on the road. Basically a startline, a "60ft" line and a "1/4 mile" line. (in practice maybe 10-15ft and 100ft???). Set up a video recorder a record a couple of passes. Play it on your computer and count the frames. Divide by 30fps and that gives you a 'launch' time and a '1/4 mile' time. A video you can play at your leisure is so much better than trying to handle a stop-watch on the day. More accurate too. Of course you have to set the camera up where it can see a span of 100+ ft which might be a bit awkward.

Maybe we should start up a "standard" test? I believe the RC drag guys use 132ft as their 1/4 mile. I don't know if they bother with a short-distance line to gauge the launch though.