Once we were racing at a kyosho race and a police drop by. He clocked my spider (stock engine (I think it is a .10 or .12), kyosho tuned exhaust using 25% fuel.) doing 73km/h on a small / mid size track (40M straight). So over 100Km for 1/8 and 1/10 is very reasonable. BTW: this is more than 10 years ago and the spider is a lot slower than the kyosho club car nowdays...