The 23C The 23B proved to be very successful in being a "giant killer" often beating cars in larger classes, but the limited road adhesion due to the narrow tyre width became apparent as the shortcoming in running with the larger cars. The 23C was developed using much wider Formula Two tyres mounted on wider 6-stud, six-spoke magnesium wheels front and rear. The body received wing-extensions to cover the wider tyres, with the characteristic 23/23B rear wings (covering the top half of the wheels on the outside) cut-out to expose the entire tyre/wheel in the side view. Lotus 23 proved a competitive, durable, and popular race car. These cars are still a mainstay of vintage racing in Europe and the United States today. Including the 23B and 23C, about 130 examples were made in period, but the popularity of the model led to many additional cars assembled from replacement and reproduction parts. The current estimate on the total number ranges between 200 and 400 excluding Xanthos and Noble. Debut at the Nürburgring The debut of the 23 was at the Nordschleife in May 1962. The tiny Lotus 23 with the newly developed Cosworth Mk.X 1.5 litre based on the Lotus TwinCam engine shot away from the field of Porsches, Aston Martins and Ferraris with Jim Clark at the wheel in the rain. Even though some cars had four times the power of the Lotus, Clark was 27 seconds ahead of Dan Gurney's Porsche after the first lap in the wet. Extending his lead on each lap until the track dried, Clark was overcome by exhaust fumes from a damaged exhaust manifold on lap 12 and crashed out. Banned from Le Mans With the sensational Nürburgring debut well publicised in the press, two 23s were entered at Le Mans in June 1962. One with a aluminium-block DOHC Coventry Climax FWMC with drivers Les Leston / Tony Shelly, and another with one litre Iron block pushrod Cosworth Mk.III with drivers Jim Clark / Trevor Taylor. The 23s failed to pass the scrutineering on several technical grounds, including an insufficient windscreen height, fuel tank capacity being too large, turning circle too large, ground clearance too small, and the spare tyre requirement not met. Fitted with a makeshift tall wind screen, all but the spare tyre issue was rectified almost immediately. The original 23 and the later 23B had 4 stud front and 6