A 1951 Ferrari 340 Barchetta, featuring coachwork by Touring, was the star lot of RM Sotheby's Monaco sale.
It made $8.2m on May 14.
The lot spent some time in collector and race driver Pierre Bardinon's famous Ferrari collection and is one of only 23 340s made.
During the early 1950s it was competed at Le Mans and has recently been restored back to this original configuration. Another 340 Barchetta realised $7.9m at RM Sotheby's auction at Monterey last year.
A 1966 Ferrari 275 GTS made $2m.
Ferrari only produced around 200 GTS', around half the number of the more popular GTB. The former is not quite as fast as the latter, but has a dedicated following of its own.
RM Sotheby's comments: "The 275 GTS was largely intended for the American market, as Ferrari convertibles had sold well in climates like California and Florida, where the attractiveness and marketability of a high-performance grand touring cabriolet had long been established…
"Its smooth and more understated lines are handsome and display an air of sophistication, discreetly hiding the race-derived V-12 that sits under the hood."
The present example has just 24,000 miles on the clock and has passed through the hands of three owners from new.
Bonhams' Monaco auction also achieved solid results, including the $8.1m paid for the best preserved example of Jaguar C-type.
Please sign up to our free newsletter to receive exciting news about classic car auctions.