BMW M635CSi: the rise of modern classic cars

By Malcolm Thorne

| 24 Mar 2025

Classic & Sports Car – BMW M635CSi: charting the rise of modern classic cars

For this feature, let’s wind back to 2017…

When news began to filter through on the grapevine, it might have sounded like an April Fool – after all, Classic Car Auctions’ two-day sale had been held over the weekend of 1-2 April – but the announcement was deadly serious.

A 1985 BMW M635CSi had changed hands at the NEC for a barely believable £100,100, establishing a new record for the E24 6 Series.

On the face of it, lot 230 was always likely to attract attention: a rare, top-spec car in a good colour scheme; one that had been well looked after by just two owners; and one that, most importantly, had covered 15,000 miles from new – meaning that it was in unusually good condition.

It was exactly the right vehicle to grab the attention of BMW fans – but nonetheless, a hundred grand, really?

The BMW M635CSi’s cabin barely shows the signs of its age

That was more than double the top estimate, and some £40k more than the combined total of the four other E24 6 Series that went under the gavel at the same sale.

So who on earth would pay so far above the odds? And, more to the point, why?

The answer to the first question is easy: self-confessed petrolhead and classic car collector William Herbert, 18th Earl of Pembroke and owner of Wilton House near Salisbury.

The why is a bit more convoluted.

“I’ve owned a lot of cars over the years,” he says, “from a Morris Marina van that I used to drive around the estate when I was 15 – and which almost ended up in the moat – to a Bugatti Veyron that I sold earlier this year because the prospect of anything going wrong with it was terrifying.

“As I’ve got older, though, I’ve been moving away from modern supercars and have been increasingly drawn to classics.”

This BMW M635CSi still has its original supplier’s sticker in the rear window

“I’d long been tempted by the 6 Series, but I didn’t want to end up getting my fingers burnt by a sub-standard car dressed up as something better,” he explains.

“Several of the classics that I’ve bought, in particular a Datsun 240Z, a BMW 3.0 CSL and a Maserati 3500GT, were described as being ‘in excellent condition’, but were in fact anything but.

“The CSL has been off the road with various specialists for seven years now, and the Maserati had to have an awful lot of work done to rectify previous poor repairs.

“In the end, I sold it because I just couldn’t justify the expense of having it finished properly.

“In that respect, the BMW offers a serious advantage: it’s basically a ‘new’ car, and needs nothing doing to it.

“To my mind, that makes it worth every penny, because I can just get in and use it; it will drive exactly as BMW intended, without me having to send it away to a specialist for two years and without having to plough a lot more money into it.”

The BMW M635CSi effortlessly blends cruising ability with pace

There is an undeniable logic to that argument, but what of the mileage: isn’t this car’s lack of use over the years exactly what makes it so special and, in turn, so valuable?

“Yes, but I didn’t buy it as a museum piece,” replies its new owner. “I’ll be using it just as the factory intended – in fact, I’m looking forward to getting it over the 20,000-mile mark so that I can stop worrying about adding to the mileage.

“That means that it will gradually deteriorate, of course, but I’m not unduly worried.

“I have a Land Rover Defender that I’ve owned since new, and which has now done 100,000 miles.

“If someone else climbed into it, they would notice the effects of all that use straight away.

“But because the ageing process is so gradual, building up slowly as the miles accumulate, to me the Land Rover hardly feels any different to when it was new.

“The same will apply with the BMW: yes, it’ll age, but I won’t notice. It’s like your children growing up.”

The BMW M635CSi’s smooth M88 straight-six engine

Look at the car today and you can see the obvious appeal.

In its day, the 6 Series coupé seemed like a vehicle of significant dimensions, but in the ebb and flow of today’s shamefully oversized traffic it looks and feels positively dainty.

Blessed with slim pillars and an airy glasshouse it has superb visibility, plus an enticing mix of ergonomic efficiency and old-world charm – and therein lies the attraction.

The best cars from this era represent a high-water mark – the point at which modern mechanicals bestowed a previously unheard-of level of sophistication, reliability and ease of use on designs that were still sensibly dimensioned and aesthetically attractive.

The awkward shock of 1970s impact bumpers had developed into something rather more harmonious, but the increasingly bloated excesses and overly complicated electronics of the modern era had yet to climb on board.

The later BMW 8 Series may finally be finding a level of credibility among classic enthusiasts, but its chunky wedge shape has none of the beauty of the Six.

The coveted BMW ‘M’ badge makes all the difference to value

As you would expect, the condition of this particular example is exceptional: it’s like being transported back to the mid-1980s to be confronted by a car that’s maybe six months old.

“I had it looked over,” says the owner today. “It’s been serviced, and they had to lubricate a few things such as the aerial and the window motors, but otherwise it’s basically untouched since the day it left the production line.”

On the day of our photoshoot, the sun is baking the lawns of Wilton House, meaning that the black leather interior of this black car could rapidly become an unbearable sweatbox, but the factory air-con still gently blows out satisfyingly chilled air.

So often, even the smartest classic cars of this era have slightly misshapen or saggy plastic trim, yet here everything feels new, solid and untouched.

In this eerily preserved machine, the clock still ticks with the same quiet precision that it did in 1985, but time seems to have stood still.

The BMW M635CSi has a complete tool tray, down to the factory cloth

Out on the road, however, the BMW certainly doesn’t stand still.

The fuel-injected, 286bhp 3453cc M88 straight-six is a wonderful unit, offering creamy smoothness when cruising or a howling dose of adrenalin when pressing on, goading you into making the most of its impressive urge.

It’s an addictive machine that blends traditional thrills with modern-day ability; spend any length of time in it and it’s guaranteed to leave you wanting one of your own.

And therein lies the crunch. Two bidders at CCA’s sale wanted so badly to own it that they were prepared to bid it up to £100,000.

A BMW M635CSi is a rare car, of course. Only 4000 or so were built, and Herbert reckons that fewer than half a dozen of the surviving UK-market cars are genuine low-mileage examples like this in such immaculate condition.

The BMW M635CSi’s sculpted rear seats

“I’d set myself an upper limit before the auction,” he says, “although in the end, of course, I didn’t stick to it…

“I’d put my paddle away and told myself that I wasn’t going to bid any higher, but then I asked myself where I was going to find another one like it, so put in one more bid.”

The story could end there: wealthy aristocrat pays over the odds for an exceptional example of a desirable mid-’80s coupé, lucky chap, good for him.

Significantly, though, the Earl of Pembroke (not to mention his undisclosed rival at the CCA sale) is not alone in his appreciation of classic cars of this era – quite the reverse.

Take note, because the ‘youngtimer’ has officially come of age.

The BMW M635CSi’s road manners are impeccable. This car’s Belfast numberplate is original, too

We’ve grown accustomed to values of chrome-era classic cars going stratospheric.

Be they Ferrari, Aston Martin, Porsche or Jaguar, those core models that were for so long tantalisingly within reach – albeit sometimes only if you applied a bit of gently twisted logic and turned a blind eye to your overdraft – have become the strict domain of the very well off.

At the same time, more affordable cars from less exotic marques – Austin-Healeys, Alfa Romeos and the like – have been dragged up with them.

Classic cars are now acknowledged to be expensive toys, and as a new generation of enthusiasts matures, an equally new generation of cars has established itself.

If you’re old enough to remember the days when, thanks to joyriders and ram-raiders, you couldn’t give away a Ford Sierra RS Cosworth (and young enough to have considered selling a kidney to finance the insurance on one then), you probably get all misty-eyed when you see one today. And you’re not alone.

This BMW M635CSi had covered just 15,000 miles from new when it crossed the block in April 2017

“People who dreamt of these cars as teenagers in the 1980s are now in the market to buy them,” says Jonathan Ostroff of Hexagon Classics, which was a BMW dealer in period and today specialises in low-mileage youngtimers from the likes of BMW, Mercedes-Benz and Porsche.

“The M635 is a rare beast, but we’ve seen positive movement in the prices of all modern-classic BMWs. Of course, due to their formerly low market values, most vehicles of that era have not been particularly well looked after.

“Many were kept outside and run on a tight budget, which ruined their condition and with it their desirability.

“Also, because they were well-built and reliable, others covered high mileages as daily drivers. As a result, although the cars are coming into their own, finding really good ones isn’t easy.”

And with scarcity comes some eye-watering prices.

The BMW M635CSi’s cassette deck and ‘computer’ scream 1980s cool

Forget the ‘mere’ £30-40k being achieved by the best Peugeot 205 GTIs and witness instead the £95k that Hexagon was asking for a sub-1000-mile Mercedes R107 500SL earlier this year, or the incredible £292,500, paid for a 1990 Mercedes 190E 2.5-16 Evo 2 at Silverstone Auctions’ Race Retro sale in 2016.

That car had covered just 1723 miles from new, but Bonhams sold another last year that had travelled a not insubstantial 48,000km, and which still went for £131,020.

“A low production number is a good indicator of desirability,” says Ostroff, “and any cars that were homologated for motorsport will be top of any serious collector’s list.”

It’s unsurprising, then, that Thornley Kelham is currently offering an 8721km Lancia Delta Integrale Evo ‘Martini 5’ for £115k, or that Silverstone made £114,750 for an 11,000-mile Ford Sierra RS 500 Cosworth in July, while rival auction house Historics sold an E30 BMW M3 Evo 3 last August for £78,400.

And if the M3 sounds cheap in this company, bear in mind that the car in question had covered some 250,000km.

‘The BMW’s clock still ticks with the same quiet precision of 1985, yet time has stood still’

If such sky-high prices sound like a depressing repetition of the spike in values of 1960s classic cars, there are cheaper cars out there that have yet to take off, but if you’re tempted, don’t hang about.

“Things are starting to move when cars reach 20 years old,” says CCA’s Simon Langsdale, who handled the sale of this BMW 6 Series.

“Performance models are what everyone wants. Fast Fords are increasingly popular, but still have potential to climb; the Escort Cosworth, for example, has yet to achieve the same level of collectability as the Sierra, but with time I think it will so it’s one to watch.

“Sapphire Cosworths are also being pulled up – we recently consigned a 29,000-mile 4x4 with a £25-30k estimate.

“I’d also keep an eye on hot hatches such as the Volkswagen Golf GTI and 205 GTI, both of which are iconic ’80s models, and all versions of the BMW E30 – especially the 325i Sport.

“The Porsche 928 is also starting to get noticed after being overlooked for too long.

“With all of these cars, buyers are looking for quality and mileage. People want the best examples, and that’s reflected in the prices.

“Top-class restorations are hard to achieve with cars of this era because the parts supply is nothing like as good as for favourites from the ’60s such as Jaguars and MGs, so properly rebuilt examples are attracting interest just as much as original vehicles.

“There’s definitely a market for both.”

So many aspects of the 1980s and early ’90s seem dreadfully vulgar today, but spend time with a classic car such as this magnificent BMW and you’re reminded that not everything about that era was awful.

“A lot of ’80s cars were rubbish,” concludes Lord Pembroke, “but the best ones really are brilliant.”

The ’80s, ladies and gentlemen, are back with a vengeance.

Images: Tony Baker

This was first in our October 2017 magazine and has been published with light edits; all information was correct at the date of original publication

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