1989 Tudor Chronograph Big Block (Ref. 79170)

The year 1976 saw the launch of the third family of Tudor chronographs, known as “Big Block”.  With the Prince Oysterdate models, the brand presented its first chronographs equipped with a self-winding mechanical movement and confirmed what the Oysterdate family had begun. Tudor offered immediately recognizable chronographs with excellent technical qualities just like the bigger brother Rolex Daytona line of chronographs. The movement uses the Valjoux caliber 7750. Having the same diameter as the manually wound Valjoux 234, 30.4 mm or 13 lines, it was 1.5 mm thicker than the latter and had a frequency of 28,800 beats per hour. Its chronograph mechanism was a highly reliable cam and oscillating pinion system.

The architecture of this new movement leveraged by Tudor at the time brought about a reorganization of the dial with the addition of an hour counter, the transfer of the group of counters towards the left of the dial, and the relocation of the date aperture to 3 o’clock. The early Tudor Chronograph references do share a lot of common traits with the big brother Rolex Daytona references including a Rolex Oyster bracelet, and 589 end-links, as well as the Rolex Trip-Lock crown and screw-down pushers. The dial on this specific Tudor reference 79170 is also very similar to the Rolex Daytona's of this era.

This 1989 Tudor Chrono Ref. 79170 is a true collector's piece and is in stunning original condition. The early Tudor Chronograph references are commonly referred to as the Tudor "Big Blocks" as the mid-case size is thicker and heavier than the big brother Rolex Daytona references.