Any Ferrari built when the founder, Enzo Ferrari, was still in control of the company is, by definition, a collectible car. Because of the glamor of Ferrari convertibles built in that era, and their relative rarity compared with coupes, there is special place in the hearts and wallets of collectors for the open-top models known as Spiders.  Examples of the model from the 1960s that is arguably the prettiest, most desirable, rarest and perhaps to become the most expensive will cross the block in Monterey, Calif., this month at sales that take place around the Pebble Beach Concours d’Élégance. The two cars, offered at different auctions, may start to settle questions about the dollar value of authenticity and provenance as well as reflect the market influence of the company that made them more than four decades ago.  RM Auctions of Blenheim, Ontario, will offer an achingly pretty 1967 Ferrari 275 GTB/4 North American Racing Team Spider, one of 10 built, which has a presale estimate of $14 million to $17 million. If the red convertible sells at the high end, it will rank as the second most expensive car ever sold at public auction.  Just down the street from RM’s sale, Russo & Steele has consigned a seemingly identical car in another classic Ferrari color, a bright shade known as Fly Yellow. But the spread in sale prices is expected to reach millions of dollars.  The difference behind this gap? The RM car was originally commissioned in 1967 by the East Coast Ferrari importer, Luigi Chinetti, and constructed by Ferrari’s official coachbuilder, Scaglietti. The yellow car at Russo & Steele began life as a 1965 275 GTB coupe; at some point its roof was artfully sheared off, and the car finished to replicate one of the official N.A.R.T. Spiders.  While Russo & Steele does not publish presale estimates, David Gooding, president and founder of Gooding & Company auctions of Santa Monica, Calif., said that this car might be expected to sell for about 20 percent of what the RM car would bring.  These conversions are referred to as cut cars, and because the supply of real Spiders were quite limited, about 100 coupes were transformed into convertibles.  In the collector car world of 2013, this sort of provenance gets tricky. Soaring values of the Spiders meant that collectors of lesser means were priced out of the market, and that inevitably led to replicas of one form or another.  According to Michael Sheehan, a Southern California Ferrari historian and broker, Ferrari is unhappy with the existence of these cars today and has discouraged some of the more prominent auction companies from consigning replicas or converted cars at the coming sales in Monterey.  Mr. Sheehan knows the world of cut Ferraris well, having performed 28 such conversions, mainly on a later model, the 365 GTB/4, known as the Daytona. In a telephone interview on Wednesday, Mr. Sheehan said that conversions were also performed by the California coachbuilder Richard Straman and an Italian firm, Autosport. Autosport, according to Mr. Sheehan, did particularly good work and had it a bit easier than the Californians.  “In those days you could walk down the street from Ferrari and buy convertible parts directly from Scaglietti,” he said, adding that Ferrari’s efforts to quash replica convertible sales has had an impact on the market. “It has definitely affected the values of the converted cars somewhat. While the cut 275 GTBs still sell for a premium over the factory coupes, cut Daytona Spiders now sell for about the same as a coupe — they used to carry a premium as well.”  RM did not say anything about any intervention by Ferrari. Alain Squindo, a vice president in the company, said that “it’s RM’s goal to always offer the best examples of the rarest Ferraris.”  Ferrari was asked to respond and did not in time for our deadline. In a telephone interview responding to the issue, Mr. Gooding said, “Ferrari has been diligent and quite vigilant about protecting what is one of the greatest brands in the world. We can understand why they would do that, and we philosophically support it and get behind it.”  The tale of two Ferraris that will unfold in Monterey should answer the question of what originality and provenance is really worth when applied to an exceedingly rare Ferrari that Road & Track referred to in 1967 as “the most satisfying sports car in the world.”
Early Ferrari convertibles are incredibly rare, and today, even the replicas cut from real Ferrari sheet metal are climbing in value. But the replica crowd asserts that Maranello doesn&#8217;t like the competition.