THE SIDELINES : British Designer Quits Ferrari Team

MARANELLO, Italy — Ferrari, Italy’s Formula One racing team, and John Barnard, the British engineer and car designer, today announced their divorce following three years of less-than-satisfactory cooperation.

Ferrari said the two sides failed to reach agreement for an extension of Barnard’s contract. Argentine Henrique Scalabroni, an aerodynamics expert currently employed by the Williams-Renault team, has been hired to direct the Ferrari division projecting and making chassis and car bodies.

Barnard, 42, who had been a successful designer for McLaren, joined Ferrari in November, 1988, on a $5-million contract. His technical leadership produced four Grand Prix victories--two in 1987, one in 1988 and one this year. Racing experts considered such results disappointing.