Collectible classic convertibles at Shannons

A host of rare and desirable Euro soft-tops are up for grabs at Shannons' Sydney Spring auction on August 29.

Heading the list is an Australian-delivered Jaguar Series 1 E-Type finished in black and powered by the 3.8-litre DOHC six-cylinder XK engine. It's not entirely original, its troublesome triple SU carburettors having been replaced by side-draught Webers. The mechanical work was carried out by noted Jaguar experts Ian Cummins and Graeme Lord, and the vendor has the receipts to prove it. According to the auctioneers the guiding price range for this car is $140,000-$155,000.

An older Jaguar sports car lotted for the auction is an American-delivered 1957 XK150 Drophead Coupe, estimated to fetch between $105,000 and $120,000. Certified by the Jaguar Heritage Trust, the XK150 was converted to right-hand drive between the years of 2000 and 2005.

Other British sports cars appearing at the auction include a Triumph TR5 with a 'Surrey Top' roof (guiding price estimated to be between $52,000 and $62,000), and a Sunbeam Alpine Mk V with 1.7-litre engine ($12,000-$16,000). The TR5 is powered by a fuel-injected inline six-cylinder engine and features an overdrive transmission. Both cars are offered unreserved. It's not really a sports car as such, but Shannons will also auction a 1950 Ford Anglia in Sydney, and the roof does fold down.

Among the 'continental' convertibles going to auction are a 1960 Mercedes-Benz 190SL 'Rennsport Recreation' roadster replica, a Mercedes-Benz 300SE from 1965 and a 1988 BMW Alpina C2 2.7.

The Rennsport Recreation started life as a conventional 190SL, before it was reimagined as a race car with the assistance of the Mercedes Heritage Department in Stuttgart. A newer engine for the Roadster has been matched to a Mazda MX-5 gearbox, and the wheels have been updated also. The current owner has raced the car, which is apparently well known in motor sport circles and has a CAMS logbook for historic competition events. Shannons believes the car should finish the auction with a bid somewhere between $120,000 and $140,000.

Shipped from the factory in right-hand drive and arriving in Australia a few years later, the 300SE Cabriolet has had a new cylinder head fitted as recently as last year. Before that, in 2011, the car's interior was retrimmed at a cost of $45,000. The guiding price range is $105,000 to $125,000.

Delivered new in 1988 by Trivett Classic Parramatta, the BMW Alpina C2 was a 320i convertible fitted with the Alpina C2 2.7 drivetrain, suspension and panels. Expected to sell for a price between $15,000 and $20,000, the Alpina is unreserved.

Finally, it's not European and it's not sporty, but the 1950 Cadillac Series 62 Convertible finished in black and trimmed in black and cream leather is certain to attract buyers for its exclusivity – fewer than 7000 sold – and its show-winning restoration. The Cadillac has been subject to a ground-up restoration by Hills Custom Cars in Taree, and retains its standard 390 CID V8, running through a four-speed Super Hydramatic auto transmission that has been rebuilt. It's anticipated to take to a winning bid between $100,000 and $120,000.