The 250 Testa Rossa was initially developed to compete in the
1957 World Sportscar Championship racing season, in response to rule changes planned for the upcoming 1958 season that would enforce a maximum
engine displacement of 3 litres. The objective was to improve on the existing 4-cylinder 2.0L
500 TR/
500 TRC Testa Rossa by integrating the more powerful
Colombo-designed 3.0L V12 as used in
250 GT series. Along with the new engine, Ferrari improved the existing Testa Rossa chassis and bodywork. As with other Ferrari racing cars,
Enzo Ferrari demanded absolute reliability from all components, resulting in a somewhat conservative design approach that aimed for endurance racing success through durability rather than overall speed.
Carlo Chiti was the chief designer during 250 TR development and his continual experimentation counterbalanced Mr. Ferrari's conservatism and led to the many revisions that kept the car competitive through 1962. Other Ferrari engineers had major contributions to the 250 TR, notably
Giotto Bizzarrini, who helped with aerodynamic improvements for the 1961 season, Included in this total are 19 "customer versions" of the 250 TR sold to independent racing teams, replacing the 500 TRC for this market. All customer cars had
left hand drive Scaglietti "pontoon fender" bodies and live rear axles. They did not benefit from the continual improvements to Scuderia Ferrari cars, although many independent teams modified their 250 TRs or purchased ex-Scuderia Ferrari cars in order to stay competitive. The helical valve springs were much smaller than previously used
torsion springs, allowing the cylinder heads to be strengthened and secured with 24
studs rather than 18 in previous 250 engines. This increased the overall reliability of the engine by improving
head gasket sealing. One spark plug was used per cylinder and the position was changed from earlier 250 designs, now located outside the engine vee between exhaust ports. This allowed for a better spark position and more efficient combustion. Piston connecting rods were now
machined from
steel billet, rather than
forged, which resulted in more stress-resistance at higher
RPM.
Bodywork and interior All 250 TRs had 2-seater
spider bodies, as did the earlier 4-cylinder Testa Rossas. At the time, this was considered the lightest and most aerodynamic configuration for a racing sports car. The first 250 Testa Rossa prototype (chassis number 0666TR) debuted at the 1957
Nürburgring 1000km. This hastily prepared prototype was based on a
290 MM chassis and had conventional bodywork by
Scaglietti very similar to that of the 4-cylinder 500 TR, except for a large hood bulge. For the 1958 250 TR, new bodywork was developed in collaboration between Scaglietti and
Chiti with several innovations on the previous 4-cylinder Testa Rossa body. Instead of the conventional fully enclosed front end, the new body had a distinctive cut-away nose reminiscent of a Formula 1 car. The protuberant central air intake was now flanked by deep channels and the headlights were set into
nacelle- or
pontoon-like fenders that enveloped each front wheel. The purpose of this design was to funnel cooling air inwards towards the
brake drums, mitigating the persistent problem of
heat-related fade. The lower body was recessed inwards behind the front wheels in order to vent heat from the brakes and exhaust. The front hood was topped with a large bulge and air intake (forward facing on some cars, reverse facing on others) to provide clearance for the vertically oriented carburetors. The rear bodywork was more conventional, including a tapered fairing behind the driver's head and two small brake lights set into vertical fins. 1959 cars that were updated to 1960 specification (minus independent rear suspension) are often designated as 250 TR59/60. The front air inlet was now split into two openings, introducing the distinctive "sharknose" or "nostril" style that was also used on other Ferrari sports racing cars such as the 246 SP and the
156 Formula 1 car. (son of the
architect with the same name). Fantuzzi's suggestion that the twin intakes would improve air penetration was confirmed by Chiti's wind tunnel testing, leading to the adoption of this style throughout Ferrari's 1961 racing cars. == Racing history ==