The 73663 Autavia remains a little under the radar, but because they are rarer than almost all of the automatic 1163 Autavia, have three sub registers, sit slightly lower on the wrist, are manual wind and have some very cool dials, they represent much better bang for your buck in my opinion. Perhaps a decade ago, the manual wind variants were out of favour as everyone wanted an automatic movement with a date window. However, I'm not sure that really applies any longer and for the above reasons and the overall reliability of the Valjoux movement, I'd choose the 73663 over the 1163 variant every time.

The 73663 was first introduced in 1972, although the Bund version only appears in one catalogue (German) and is thought to have come to market a little later in 1974. They were advertised in the catalogue as having a "Military Look" and were priced at 395DM. The use of the Valjoux 7736 allows not only for the three sub register layout, which is so loved by collectors, but it also allows for a shallower case because the Calibre 11/12/14/15 automatic movements were deeper to allow for their automatic complexity. They also have the crown on the "right" side (right both in terms of left/right and right as in correct because most people find left-sided crowns unwieldy). These small things matter and help make a difference to the overall balance, because the watches from this period represented a sea change in style and weight being much larger (measuring 42.5mm) than their 1960s cousins. 

Obviously, the dial was designed with military use in mind and some have been observed with military markings (although most are civilian). I would surmise a small batch was made for the military and Heuer was never wasteful so using the remainder for public retail would have been the obvious course to take. The all-black dial with contrasting green numerals is striking and contrasts well with the cream lume in the hands and the applied lume dots at 3,6,9. I think it is one of the most beautiful of all the 1970s Autavias - this dial really pops! Occasionally this reference is seen with green lume in the hour and minute hands, but this is aftermarket work to match the numerals, not how they were originally born. Lastly, note that this is one of only two Autavias to feature the bund chronograph sweep hand, the Diver 100 being the other variant. 

The serials for all of the 73663 Autavia form a block that spans 1996xx - 2025xx and from this we can deduce that Heuer allocated serials for circa 3000 units. Of course, not all may have been produced but this gives us the maximum possible which is a good starting point. By far the most common of the Autavia 73663 variants is the "Siffert colours" variant, with approximately 50% of this dial being documented of the observed market. I would therefore suggest that fewer than 300 of the remaining dial options were produced, which actually makes these watches much rarer than might be thought and, as I said before, a little below the radar. Values wise the 73663 Bund might range between £4000 for an entry level example to £10000 for the very best, although they seldom come to market.

If you would like to learn more about the myriad of Heuer Autavia chronographs between 1962-85 then click on the link below to preview and order the collector reference book.