77mph is the speed record for poo-powered buses, apparently
 

Britain has several players in the fledgeling poop-bus industry, including one that literally shows people pooing, but a gauntlet has just been thrown by the town of Reading. Its very own cow manure-powered model, dubbed "Bus Hound," ran the track at...

http://www.engadget.com/2015/05/21/m...=rss_truncated