The 904 was the first Porsche to use a ladder chassis and fibreglass body, appearing more like a specialist racing car than the modified sports cars typical at the time, and was painted white. The fibreglass body was bonded to its steel chassis for extra rigidity, and achieved a drag coefficient of 0.34. While many German race cars had used unpainted aluminium bodies since the famous 1934 Silver Arrows, most 904s were painted silver, the modern German national racing color. Unusually for Porsche, the two-seater bodies were provided by contractors, which would later become standard practice among race car builders. The 904's fibreglass body was made by spraying chopped fibreglass into a mold, the amount sprayed often varied in thickness over the shape of the car and as a result the weight of the various cars was somewhat inconsistent. Race-prepared four-cylinder 904s weighed in at approximately 1,443 pounds (655 kg) and the low weight gave the 904 the ability to accelerate to from a standstill in less than six seconds (using the standard rear gear, which was typical at Sebring) and to reach a top speed of (with the 3.362 ratio). Frontal area was only .