Smart Buys Quentin Willson charts the rise of the rarity that is the AC 428, tips the slab-sided Mercedes W140, and recommends the XJ12C, a Bl-built Jaguar. Yes, really.

Quentin on why an AC, a Mercedes, a Lamborghini and, yes, a Bl-built Jaguar should all be on the canny buyer’s radar

‘Beautifully styled by Pietro Frua and good for 145mph, the AC 428 deserves to be recognised as the sexiest Anglo-american hybrid of them all’

‘When you look at the prices of Cobras and Aces the AC 428 still seems out of step with the market.’

I’ve tipped the 428 as a stellar investment before and time has proved me absolutely bang-on. Back in 2012 Bonhams knocked down a mint red 1969 coupé with 35k miles for £77k yet Hexagon Classics has recently sold a restored ’71 in silver for close to £300k. That’s a solid jump in four years but AC built only 80 428s – 51 coupés and 29 convertibles – so they’re actually more exclusive than a factory-built Ferrari Daytona Spider. Beautifully styled by Pietro Frua and good for 145mph with 60mph in less than six seconds, it deserves to be recognised as the sexiest Anglo-american hybrid of them all. Keith Moon owned one along with Rob Walker; and the first prototype, a rare alloy-bodied convertible, starred in early Avengers TV episodes.

Priced at £5573 in 1968 they were more expensive than an Aston Martin DB6 and, thanks to the Seventies oil crisis and a 15mpg thirst, production was halted in 1973. Most owners know how special their 428s are and nice cars rarely come on to the open market. But even at over £250k I think they’ve still got some

appreciating to do. The convertibles are the most wanted, manuals are very rare and there were only 12 left-hookers built. Sixty-one of the 80 cars built survive so somewhere there could be a neglected 428 sitting ready for discovery. Understand how special, gorgeous and fast the 428 is and you may come round to my way of thinking that these cars could one day hit £500k. Their rise in value has been consistently steady and it’s hard to believe that in 2003 H&H sold a ’69 one-owner 37,000-mile convertible for just £23,000.

When you look at the prices of Cobras and Aces the 428 still seems out of step with the market. All the credentials are there: tiny production figures, epic performance, stunning lines and a fascinating backstory. If only we’d known all this when that Avengers convertible prototype, LPH 800D, was sold in 1970 for just £3250. Hindsight can be a depressing thing.

‘Buyers are slowly waking up to the rarity and potential of the XJ12C’

British Leyland weren’t really the right people to build a V12 coupé. But against all odds they produced a quick, handsome 12-cylinder two-door and even went racing with it. The Broadspeed V12 coupé was a Group 2 racer, which in the hands of Derek Bell outpaced BMW’S iconic CSL. But, like the road cars, the Broadspeed XJ12C’S big problem was reliability.

Only 1873 Jaguar XJ12CS were built and just 407 Daimler Double Six versions so they’re rare and becoming highly regarded. But there’s still some pricing confusion. Jaguar West London recently sold a red ’77 Daimler Double Six model with 70k miles, restored in the Nineties but needing ‘light recommissioning’ for just £8995 – cheap, given that in 2016 H&H sold a ’75 XJ12C with 54k for £26,880. Buyers are

slowly waking up to the rarity and potential of these V12 coupés helped by the £62,000 paid for the New

Avengers project that needed absolutely everything. In 2008 Bonhams managed £80k for one of the Jaguar Group 2 works cars – that’s got to be worth £400k now.

Really nice standard XJ12CS can now make up to £50k, like the white ’76 concours example being sold by CMC in Bridgnorth for £45,000. But many were neglected and just scrapped because of rust and that prodigious 12mpg thirst so there are still likely to be barn-finds out there. However, restoration costs will be ruinous and you’d be better oé buying a mint, restored car. Really original or well-cared-for cars are attracting serious interest but I think even at £40k to £50k they’re still real value. I remember thinking exactly this when I saw the world’s best XJ12C – a multiple concours winner – at Silverstone’s NEC sale this year. A stunning ’77 in Carmen Red with just 43,000 miles and total history it sold for a very reasonable £43,875. That’s less than half the price of a restoration – and you get the trophies and concours certificates for free.

‘Bag a good 600 W140 now and you’ll be buying one of the most undervalued Mercs of all’

Why don’t we love the Nineties V12 Merc 600 S Class? Bypass the limiter and they’re good for 179mph, sixty comes in 5.5sec, interiors are lusher than Trump Tower and in 1991 they cost their tycoon owners £100k. But while prices of the 6.3s and 6.9s have gone into orbit you can still pick up a finely fettled 600 SEL for less than £15k. Total Vehicle Solutions in Hampshire has a silver ’92 600 SEL formerly owned by the Sultan of Brunei’s son with 86k and ‘enormous history’ for £8995 while Ron Hodgson Specialist Cars in Wigan has a blue ’91 with virtually the same mileage for £12,995. Most 600s have soft-close doors, doubleglazing, heated memory seats, rear window blinds and even little chrome electric wands that rise from both rear wings when you select reverse to aid parking. And while the slab-sided W140 doesn’t have the same classic cachet of the 6.3 and 6.9s these V12s are a fifth of the price, much faster, smoother and better equipped. The owners I’ve spoken to haven’t had the sort of nightmares you’d expect from such a complex machine. The door and boot vacuum pumps can fail, they get through bottom ball joints (and tyres) regularly and oxygen sensors misbehave. But most of the problems are small pipes, hoses and bushes. Change the oil every 7500 miles and that M120 lump will run for ever and ever.

See a 600 SEL on the road – a rare sight now – and you know you’re in the presence of real greatness. The lines are looking cooler every day and if you can find one in black it radiates head-turning authority. But finding a low-mileage historied example could take months as the DVLA only has 20 taxed and 50 SORN’D 600 SELS on its mainframe. But if you bag a good one you’ll be buying one of the most undervalued classic Mercs of all – a situation that’s bound to change soon.

‘See a 600 SEL on the road – a rare sight now – and you know you’re in the presence of real greatness’