The 14th century Mongol bow from Tsagaan Khad (Cagaan Chad) is perhaps of such draw weight. Supposedly, replica made to match the original in dimensions vary from about 120lb to 180lb. I haven't seen accurate dimensions for the bow (in particular, the thickness of the bow), so can say how reliable such reports are.

There is, however, an excellent overview including reliable estimates of draw weight, for 46 Ottoman bows (from the Topkapi Palace Museum and the Military Museum in Istanbul). These bows have an average draw weight of 120lb (and median draw weight of 115lb). Of these 46 bows, 7 have draw weights of 160lb and higher. A histogram showing the draw weights of these bows can be seen at https://i.imgur.com/rR3SsPt.png

Considering these bows, it does seem that Mongol bow draw weights could reach (or exceed) 166lb, although it is likely that the average draw weight was lower (perhaps 100-120lb for military bows).

References:

The Tsagaan Khad bow: B. Ahrens, H. Piezonka, G. Nomguunsuren, Buried with his Bow and Arrows: The exceptional cave burial of a 14th century warrior at Tsagaan Khad mountain, Mongolia. In: Ta La (Hrsg.), Ancient Cultures of the Northern Area of China, Mongolia and Baikalian Siberia, Band 2. Hohhot 2015: 683-692. http://www.academia.edu/17150484/Buried_with_his_bow_and_arrows_The_exceptional_cave_burial_of_a_14th_century_warrior_at_Tsagaan_Khad_mountain_Mongolia._In_Ancient_cultures_of_the_northern_area_of_China_Mongolia_and_baikalian_Siberia_Part_Three_Historical_Period_Bejing_2015_683-692

Ottoman bows: A. Karpowicz, "Ottoman bows -- an assessment of draw weight, performance and tactical use," Antiquity, vol. 81, pp. 675­-685, 2007.