Green’s Dictionary of Slang

1. (US) anything, or anybody, considered exceptional, both positive and negative; thus stem-winding adj., outstanding, exceptional.

1890–1904		Farmer & Henley Sl. and Its Analogues.
1892		A.C. Gunter Miss Dividends 68: ‘Ain’t he a stem-winder, though?’ goes on the boy. ‘He was the most popular man on the line when it was built.’.
1906		S. Ford Shorty McCabe 110: ‘It [i.e. a game] was a stem-winder,’ says I. ‘Sir Peter was off side most of the time; but I don’t carry no grouch for that.’.
1909		‘O. Henry’ Roads of Destiny 190: There’s a new examiner over at the First and he’s a stem-winder. He’s counting nickels on Perry, and he’s got the whole outfit bluffed.
1919		D. Runyon in Pittsburg Press (PA) 28 June 12/4: The Australian ballot system of judging this fistic election [...] has knocked betting a stem-winder.
1926		in J.F. Dobie Rainbow in Morning 85: He’s a stemwinder and go-getter.
1931		(con. 1918) E.W. Springs Rise and Fall of Carol Banks 247: ‘What brings you East?’ I inquired. ‘Oh, a stem-winding débutaunte,’ he confessed. ‘She’s been causing fever all over town.’.
1940		Montgomery Advertiser (AL) 22 Aug. 11/4: Bob represents a stem-winding liquor concern with a stem-winding product.
1948		S.F. Examiner 12 May 13/5: I would say it costs a thousand smackers per day to operate a stem-winding yacht, rain or shine.
[1953		Delta-Democrat Times (Greenville, MS) 14 Nov. 4/2: He is one of the few old-school stem-winding orators still in Congress].
1955		Boston Globe (MA) Fiction Mag. 18 Sept. 2/4: Chiqui, for all its squalor and refuse and stem-winding blue bottle flies, was a wonderful vision.

2. a battered old car [with ref. to the ‘historical’ image of such watches].

1947

S.J. Perelman ‘The Longer the Lip’ in Keep It Crisp 152: You mean the stem-winder in the driveway? [...] That’s not a car – that’s transportation!

3. see key winder under key n.¹