I don't think that anyone envisaged that such very high speeds would be attained at Le Mans. The fastest recorded on the old Mulsanne was 407kph ( 263mph ) in 1988. Jaguar driver Norman Dewis maintained that he achieved 194mph in 1955 in a long-nose D-Type. Chicanes are usually located after long straights and are placed by circuit designers to prevent vehicles from reaching speeds deemed to be unsafe. A combination of high speeds and high downforce led to tyre and engine failures, some with disastrous results. Along with other circuit design changes, there are now several chicanes, including two chicanes on Mulsanne and one ( Ford Corner and Ford Chicane ) leading to the start/finish line ( the 1955 accident area ) In addition, the FIA decreed that it would no longer sanction a circuit that had a straight longer than 2km ( 1.2 miles ), Hence the introduction of the chicanes on Mulsanne and our own Caltex Chase at Bathurst prior to the WTCC race there in 1987.