Had a few Cox vehicles back in the mid 70s, the Vega funny car, the trike, a worm gear drive Baha bug, I remember setting up the string for the dragster to run on, you put a couple of nails in the asphalt 40-50ft apart, run the string between the two and put a knot about 3/4 down the run to deploy the chute and shut the engine down, we fired it up and set the needle valve, the little nitro methane fueled two stroke diesel was singing, we set it loose and stood back, it shot down the string, blew past the knot and ripped the nail out of the parking lot, we stood there as our Cox Dragster smoked it's little tires in this huge circle we were standing in the middle of, we side stepped the string when it came around, I remember it being too fast to try to catch so we just let it run out of fuel after a minute or so......................Tom.