Well that was an interesting question. I just checked the Cub parts web site looking for what is different between the engine in the 1440 and the 1641, block, heads, crank shaft, cam, pistons, flywheel, carb, timing gear and intake manifold are the same. So my guess is that the 14 & 16 are the same engine and this is another case of marketing like the M15 in the 1541 that is really an M18. That said is the 1440 really a 1640?
The V-Twin Vanguard in my opinion is possibly the best air cooled gas engine on the market today. The Vanguard is not built by B&S it is actually built by Daihatsu Briggs & Stratton (DBS).
http://en.wikipedia.org/wiki/Briggs_%26_Stratton
I like the Vanguard enough that I repowered my 1210 that had a Kohler M12 in it with a 16HP Vanguard.
