There are two series of the Rolex Cosmograph Daytona. The original series, produced in small quantities from the early 1960s to the later 1980s, has a four-digits model or reference number, for example the reference 6263. This original series eventually became iconic but in very short supply in the early 1990s, which led to a second series to meet demand. This second series was a Zenith modified movement, the five digit series movements noted by dropping the "1" from the current 6 digit code is notably the most accurate of all movements whose pedigree is in the famous Zenith "El Primero" movement. This movement was originally manufactured and released in the '60s and is still the highest VPH mass produced movement on the market at 36,000 VPH. The "El Primero" movement is often considered the hallmark of chronographs for accuracy and reliability. Rolex purchased these movements for the Daytona and then modified the movement from 36,000VPH to 28,800VPH and made a few other subtle changes. These later series Daytonas prior to in-house movements were produced from 1988 to 2000 and represent the time period where Rolex Daytonas really began cult status, due to its limited production, accuracy, reliability and limited supply as they were coming from Zenith. This Zenith based movement is often considered more accurate and reliable than any other movement in the Chronograph space, including the current in-house Rolex Daytona model. The current series, the Rolex in-house made movement, has a six-digit reference number, for example reference 116520. The new six-digit Daytonas are certified, self-winding chronometers with chronograph functions. Rolex was, and remains today, a sponsor of the Rolex 24 at Daytona race at the time, and named its chronograph watch after that famous race.
Although Rolex continues to manufacture a version of the "Daytona", the rarest versions of the Rolex Daytona are the first versions, those whose reference number contains four digits, for example the 6238, 6239, 6240, 6241, 6262, 6263 6264 and 6265 References, produced from 1961 to 1987. The 6238, 6239, 6241 and 6262 References were the first versions, and were not "Oyster" versions, they did not have a screw down winding crown or screw down timing buttons. The movement used was a manual wind Valjoux cal. 72, named the Rolex Cal. 722. The 6263, 6264 and 6265 References were produced commencing 1970, were Oyster versions with screw down crown and screw down timing buttons. The movement used remained based on the manual wind Valjoux cal. 72, but with some refinements, and was called the Rolex Cal. 727. These Daytonas are very rare and very collectible. The movement has proven to be exceptionally reliable and accurate. In fact, the Cal. 727 was certified as a chronometer in some cases.
The rarest Daytonas are those with the so-called "Paul Newman" dial. Its distinguishing features are subtle and often unnoticeable to the untrained eye. First, a Paul Newman dial must be in a Reference 6239, 6241, 6262, 6263, 6264 or 6265 watch, installed by Rolex Geneva as original. All of these References had acrylic domed crystals. That aside, the sub-dials (the dials that are the opposite or contrasting color of the main dial) of a Paul Newman dial have block markers instead of lines, will have crosshairs across each sub-dial meeting at centre (unlike the normal Daytona), and the minutes sub-dial placed at 9:00 is marked at 15, 30, 45 and 60, whereas a normal Daytona dial is marked at 20, 40 and 60. The dial may or may not have the word "Daytona" written on the dial above the hour sub-dial located at 6:00. The dial came in four color and layout combinations, and was installed as an option by Rolex on the Daytona line of watches in the Reference 6239, 6241, 6262, 6263, 6264 or 6265 watches. The watch has been out of production since the early 1970s, and Rolex is not able to supply any replacement version of it.
The original Daytona watches were not in demand when produced, and were inexpensive, but have gained rapid esteem among collectors, are known as the "Holy Grail" of collectible watches and fetch considerable prices at auction.[