Aston Martin DB4 Series 3

About the Aston Martin DB4 Series 3

The DB4 was manufactured from 1958 until 1963. It was an entirely different car from the DB Mark III it replaced, though the 3.7 L engine was externally visually related to the 2.9 L unit found in that car. The DB4's unique design and performance would later form the basis for future Aston Martin classics, such as the DB4 GT Zagato, the Lagonda Rapide 4-door saloon, and its ultimate replacement the Aston Martin DB5. There were five "series" of DB4s. The Series III cars differed from the earlier ones in having taillights consisting of three small lamps mounted on a chrome backing plate. Earlier cars have single-piece units and the last Series V cars of September 1962 have similar taillights but recessed. The Series V also has a taller and longer body to provide more interior space, though the diameter of the wheels was reduced to keep the overall height the same. The front of the Series V usually was of the more aerodynamic style as already used on the Vantage and GT models, a style that was later carried over to the DB5 cars.

The 3.7 L (3670 cc/223 in³) engine, designed by Tadek Marek, was a double overhead cam straight-6, with cylinder head and block of cast R.R.50 aluminium alloy, a further development of the earlier engine. The engine was prone to overheating initially, but the 240 hp (179 kW) produced by the twin-SU carburettor version made buyers forgive this unfortunate trait[citation needed]. Servo-assisted disc brakes were fitted all round: early 11.5 in (292 mm) Dunlops were replaced by Girlings. The independent front suspension used ball-jointed wishbones, coil springs and rack-and-pinion steering. The live rear axle also used coil springs and was located by a Watt's linkage. The normal final-drive ratio for British and European use was 3.54:1: in the United States the ratio was usually 3.77. Customers wanting a car with an especially high top speed could choose a 3.31:1 ratio.

A car with the British standard 3.54 final drive ratio tested by The Motor magazine in 1960 had a top speed of 139.3 mph (224.2 km/h) and could accelerate from 0-60 mph (97 km/h) in 9.3 seconds. A fuel consumption of 17.7 miles per imperial gallon (16.0 L/100 km; 14.7 mpg‑US) was recorded. The test car cost £3967 including taxes.

There were five "series" of DB4. The most visible changes were the addition of window frames in Series II and the adoption of a barred (rather than eggcrate) grille in Series IV. The Series III cars differed from the earlier ones in having taillights consisting of three small lamps mounted on a chrome backing plate. Earlier cars have single-piece units and the last Series V cars of September 1962 have similar taillights but recessed.The Series V also has a taller and longer body to provide more interior space, though the diameter of the wheels was reduced to keep the overall height the same. The front of the Series V usually was of the more aerodynamic style as already used on the Vantage and GT models, a style that was later carried over to the DB5 cars.

Steel chassis with aluminium body
Engine : all alloy straight six dohc
Transmission : Four speed manual rear wheel drive
Suspension : Front coil springs, double wishbones, telescopic dampers, anti-roll bar. Rear has a live axle, coil springs located by a Watts linkage with lever arm dampers
Brakes : discs all round with servo
Steering : Rack and pinion