1931 Bentley 4½ Liter Supercharged Boattail

This 1931 Bentley 4½ Liter Supercharged Boattail sold for $4,510,000 at the Gooding auction on August 19, 2007, during the Pebble Beach weekend.

The “vintage” or “W.O.” (after its creator’s initials) Bentley lasted from the eponymous company’s 1919 foundation until its bankruptcy in July 1931, victim of the Wall Street crash, a glamorous but costly racing program, and management that was arguably more concerned with building than selling the ultimate motor car. Fast, large, and expensive, the vintage Bentley reflected W.O.’s early training as a railway engineer, causing rival Ettore Bugatti to remark that “Monsieur Bentley builds the fastest lorries in the world..” To the patriotic British motoring public, these “lorries” were a source of pride comparable to Duesenberg in the States; 80 years later, the current generation of admirers are usually successful entrepreneurs rather than impecunious schoolboys, hence the increase in the cost of ownership compared to the original factory price list.

Of all vintage Bentleys, it is ironic that the most sought-after model should be the supercharged 4 1/2 Liter. In her definitive Blower Bentley book, the aforementioned Clare Hay observed: “The impetus behind the Blower Bentley came almost entirely from one man-Sir Henry Birkin, Bart., known to all and sundry as ‘Tim’. Birkin is perhaps the most interesting of the ‘Bentley Boys’… W.O. himself said of Birkin that ‘His gaily vivid, restless personality seemed to be always driving him on to something new and spectacular, and unfortunately our 4 1/2-liter car was one of his targets.'”

W.O. famously disapproved of supercharging, remarking “there’s no replacement for displacement.” Birkin, however, was convinced otherwise, and with the backing of wealthy young heiress Dorothy Paget, he set about building a handful of 4 1/2-liter cars to “blown” (i.e. supercharged) specification for racing. The resulting four Blowers (plus one that never raced) are today referred to as the “Birkin Team Cars” and are perhaps the most valuable Bentleys in existence. In order to homologate them for the all-important Le Mans 24 Hours, Birkin had to persuade Bentley Motors to build 50 production examples. Conveniently, by 1928, the company was controlled by 33-year-old Woolf “Babe” Barnato, a sporting client who in 1925 had become the company’s financial savior (and chairman), with W.O. relegated to the role of joint managing director. This was the background to the agreement signed in October 1928 between Bentley Motors, Tim Birkin, and 28-year-old consultant engineer Amherst Villiers (first cousin of Winston Churchill), who was entrusted with supercharging the 4 1/2.

Meanwhile, Bentley Motors continued development of a high-performance version of its flagship “Big Six” model, the resulting Speed Six becoming the firm’s front line racing weapon from the 1929 season onward. In the event, it was the Speed Six that cemented the Bentley legend on the track, winning the Le Mans 24 Hours in both 1929 and 1930, while poor Birkin’s Blowers failed to win a single major race.

Perhaps its most memorable achievement was the 1930 French Grand Prix at Pau, which saw the quixotic spectacle of Birkin’s stripped-down yet towering Blower chasing no fewer than 16 GP Bugattis, eventually finishing second to “Phi Phi” Etancelin’s Type 35C. Birkin later commented: “It was the last of all the big races, in which I ever had any success with the old green Bentleys, and the most enjoyable.”

The production Blower didn’t fare much better. Originally priced at £1,475 ($6,689), this was cut in January 1931 to £1,150 ($5,215), just £100 more than the standard 4 1/2 Liter, in order to shift unsold chassis. In the event, London Bentley agent (and racer) Jack Barclay was obliged to take a number of them in settlement when Bentley went under, so 50 Blowers were indeed built, and 50 Blowers were (eventually) sold, but the whole project cost Bentley a great deal of money it could ill afford.

Our 1931 Bentley 4½ Liter Supercharged Boattail, SM3916, was supplied to Barclays and fitted with unusual two/three seater coachwork by the most prestigious British coachbuilder of the day, Gurney Nutting, a favorite of Woolf Barnato. As Gooding’s catalog observed, their interpretation for SM3916 bore some resemblance to the chairman’s own Blower (SM3909), although its lacks the latter’s racy helmet wings and rear screen. In her original 1986 book, Bentley, The Vintage Years, Claire Hay noted that SM3915 and 3916 were “built as cheaper copies of SM3909.”

In fact, there were probably three “less expensive” 2/3 seaters inspired by the Barnato Blower-one red, one blue, and one green-the car pictured being the last and the only one to survive unmolested. It may not have quite the sex appeal of a Birkin team car, but do your homework and it won’t take you long to discover that an original Le Mans-style four-seater Blower is something of a rarity, many having been ordered with the rather more luxurious bodywork fashionable at the time and the final cars bodied down to a price. Just four “semi-Le Mans” Vanden Plas tourers were built for favored clients, and together with the Gurney Nutting 2/3 seaters, any of the survivors would be about as good as it gets for a production Blower.

So where does that leave us on price? Well, a Birkin team car would probably command well upwards of $6 million today. The best surviving Speed Six racer (2nd place at Le Mans 1930) was sold at Christie’s in 2004 for $5,109,665, blitzing its then-estimate but almost certainly worth more today. Two rebodied Blowers were sold privately last year for less than $2 million, whilst an original Vanden Plas-bodied “long wing” tourer (not the racy one) is believed to have changed hands last spring for $3.5 million. Offered from the estate of the late Ann Klein, a well-liked and respected figure in U.S. collecting circles, the Green Hornet had most of the right ingredients: long-term ownership (a speculator isn’t making a fast buck), good looks (by British standards anyway-let’s call it “rugged”), and absolutely no-stories originality (no sniggering from armchair experts at the next event it attends). All it really lacked was racing history. Vintage Bentleys may not be as fashionable as their Latin counterparts, nor as easy to understand (or drive), but they exude an honest, “old money” charm that suggests their owners have nothing to prove and discreet good taste.

Like the cars themselves and the buyers they usually attract, the market for W.O. Bentleys is steady and not prone to nasty surprises. Considering their place in automotive history, and the motoring doors they open, their recent appreciation seems well-founded, and I would say the European buyer of the Green Hornet paid spot-on the money. Looks like Tim Birkin had the last laugh after all.