Renault Vel Satis guru Oliver Hammond piqued my attention via Twitter a while ago because of his efforts in building up a VelSat community.

His Vel Satis forum site is ever-more popular and it remains a curio I dip into regularly, not least to see what’s up for sale and whether prices have finally dropped down to a level that would warrant an impulse purchase (not yet).

And why my fasciation with the failed French 5 Series rival? Because of a happy week back in 2002, when I took one down to Newquay for a week’s holiday. Quite something for a still-green writer back then, stymied by the 25-and-over insurance rules of many press offices. Renault was one exception. Bingo: the keycard to a Vel Satis 3.0 V6 dCi Initiale was mine for a week.

Memories? Mainly of its might. A big car, is the Vel Satis, accentuated by its outlandish design and super-bold le Quement detailing. Like the MkII Megane, it’s dating now, but there’s still no denying its presence – back then, resplendent in road test dark green, it looked amazing. Every inch the epitome of avant-garde French executive travel.

If anything, it felt even bigger from the inside. The huge seats were mounted very high atop their electric multi-adjust motors, whose variability even extended to a split seatback – the upper half could be raked independently to the lower. On the 300-mile trek to Newquay, this gave me no end of entertainment.

It was a distraction from all the glances I got. Seriously, everyone (so it felt) looked at us. I’d never driven anything that was such a headturner and, even now, few things have roused so much attention on the road. The Vel Satis was amazing, so it seemed: a pink Ferrari would have roused less attention.

Luckily, we were cocooned from it within, savouring the Makintosh-style wood trim and details, decent in-car audio quality and the surge of the big diesel. Something this easy and torquey was still a refreshingly new experience for me back then, and the satisfaction I felt remains clear in my mind. My love of torque may even have been cemented on that trip.

It wasn’t perfect. The ride could be taut, trim could creak in sympathy and lifeless steering certainly didn’t help pilot the big beast round Cornwall’s narrow streets. But I still loved it – still love it. The MSN Cars Renault Vel Satis road test talks about the minutiae, but the general vibe was positive.

Yes, it bombed, but it wasn’t through lack of character which, as a result, certainly infused goodwill amongst a loyal few. Still does, too: so, power to you, Oliver. Give me a shout when a cheap dCi V6 turns up, won’t you..?

+ Renault Energy dCi 130: F1 on the road

+ Renault Raider is back

+ The auto brands Lotus has links with

Lotus is the car company that wants to be associated with everyone at the moment. 

Or should it be Lotus is the car company everyone wants to be associated with?

Either way, it’s great PR for the long-fledgling Norfolk brand, which suddenly has worldwide exposure it could never have imagined a year ago. If Lotus is eager for a bigger share of the limelight, it’s certainly getting its wish.

But given how every day seems to bring some sort of new Lotus linkup, it’s perhaps time for a recap: just what are the car firms whose name Lotus sits alongside today?

Well, here’s a list. Some are stronger than others, but all are focused on one thing – maximising the value of that world-famous Lotus roundel.

Colin Chapman would, I’m sure, be chuffed to bits.

Lotus

Lotus road cars is the focus of huge investment, activity and interest. Parent company Group Lotus wants to become a supercar rival to Ferrari and Porsche: after the clumsy way it launched these intentions at the Paris Motor Show 2010, it is now slowly winning acknowledgement that the plans could have merit – and COULD actually work.

Lotus-Renault

Renault, faced with falling market share, has pulled back on its F1 exposure in recent years. After selling a stake in the team to Genii Capital, Renault sold its remaining 25% stake to Group Lotus. The F1 cars are thus called ‘Lotus Renaults’.

Lotus-Caterham

Entrepreneur Tony Fernandes purchased the rights to use the ‘Lotus Racing’ name in 2009, successfully running the team in F1 last year. The team was renamed ‘Team Lotus’ for 2011. Group Lotus brought a court case against Fernandes this year, which culminated in the ruling that Fernandes can continue using the Team Lotus name. In the meantime, Fernandes also bought Caterham Cars. Team Lotus is now thus carrying ‘Caterham’ branding, just as the Renaults carry ‘Lotus’ branding.

Lotus-Proton

Proton owns Lotus, and has used its British sports car division’s name on several models in the past. ‘Engineered by Lotus’ has graced the back of models such as the Proton Satria GTI, after it commissioned Lotus Engineering to re-engineer the cooking budget hatchbacks.

Lotus-Youngman

Youngman, a Chinese bus manufacturer, entered passenger car production with a new brand, Europestar. These were rebadged Protons, which Lotus Engineering developed into Chinese-market models with a series of revisions. Youngman, drawn to the allure of the Lotus brand, has been increasingly associating itself with (and marketing itself as) Lotus, despite the link being with Lotus Engineering, not Group Lotus.

Lotus-Saab

Youngman-Lotus, in alliance with car distributor Pang Da, has secured a €245m equity stake in Saab and signed Memorandums of Understanding for further alliances subject to approval by authorities. Chinese interests in Saab are thus likely to grow, as further investments are made in the Swedish brand.

The Lotus name has links with yet more makers too: these are a bit more tech-specific but are still a rare public showcase of Lotus Engineering links with another manufacturer. Here’s a few examples:

Lotus-Tesla

The most well known recent Lotus collaboration: Lotus provides around 40% of the overall content of a Tesla Roadster, the world’s first electric sportscar. It doesn’t wear Lotus badges but even casual observers know the link.

Lotus-LTI

Lotus Engineering was part of a collaboration that’s developed a hydrogen fuel cell taxi, led by cash from the government Technology Strategy Board. Lotus designed the full propulsion system, including the fuel cell engine.

Lotus-Jaguar

The two worked together on the Limo-Green project that created a Jaguar XJ EREV. Lotus provided its 1.2-litre range-extender engine, created with funding from the TSB. This has three cylinders, 47hp, simple construction and weighs 56kg. It’s been designed specifically to drive an alternator, to generate electricity – and is thus better than the Chevrolet Volt’s car-derived 1.4-litre range-extender motor.

Quite a list. And these are just the public ones. Group Lotus’ consultancy division, Lotus Engineering works with many other car manufacturers besides, on below-the-line solutions to specific needs, most obviously in vehicle dynamics.

Lotus Engineering, for instance, is said to have worked on the latest Nissan GT-R, and also has long associations with GM/Vauxhall (the excellent Vauxhall Corsa VXR was Lotus Engineering-developed, and thus way better than the Vauxhall Corsa SRi it was derived from).

Frankly, Lotus is everywhere. It always has been – but the fact it’s so omnipresent hasn’t always been advertised so well. Finally, both the allure of and expertise behind the name are gaining recognition, which means lots are now keen for some of the Lotus limelight.

Not all these collaborations are perfect, but all of them DO have some genuine Lotus link in some way. Question is, which are the lasting Lotus links and which are the Lotus liabilities?

UPDATE

Lotus-Top Gear

Group Lotus Motorsport designed the original Top Gear test track, which stars in reasonably priced cars have competed with The Stig upon for years. Now, the link is being reinforced: Lotus is designing the new Top Gear Live test tracks. Well, the links don’t have to be literal car ones…

+ The Lotus position: confusing

+ Renault Energy dCi 130: F1 on the road

+ Pirelli tyres: a key into F1

Renault is one of the most successful F1 engine makers of recent years.

Be it Williams, Renault (Lotus?) itself or now Red Bull, the firm’s Formula 1 engines have powered countless race wins, plus a hefty haul of World Driver and Constructor titles.

All this expenditure must be justified though, which is why car makers oft witter on about their F1 programmes driving what happens on the road. Indeed, we all think: like a Renault Clio 200 really is about to get a 2.4-litre V8.

But finally, Renault has revealed exactly how F1 can help road car programmes – with the headline-grabber being it’s giving us the most powerful (yet green) 1.6-litre diesel engine ever sold. Cue the 1.6 Energy dCi 130: the most advanced mid-range diesel yet built?

Facts

Renault wants to cut its range CO2 average from today’s 135g/km to below 120g/km in 2013, and below 100g/km come 2016. To do this, it needs new engines, with big incremental CO2 falls. Renault says its new Energy engines must cut CO2 by 30-40g/km over the motor they replace.

The R9M 1.6 Energy dCi 130, on paper, does this: 30g/km less CO2 and 20% better fuel economy than the 1.9 dCi 130 FQ9 it replaces. Design work started in 2006 and it was a clean-sheet design that generated 30 patents.

Of its 264 components, 75% are new: the rest mostly come from the MR9 2.0 dCi 150. There are also six specific CO2-reducing technologies, that together drop CO2 by that 20% total.

F1 link

The F1 link is genuine. Engineers from RenaultSport F1 in Viry-Chatillon worked with road car engine designers in Rueil to transfer F1 tech to the road.

Philippe Coblence managed the R9M project at Rueil – and formerly did the same at Viry-Chatillon for F1 engines in the early 2000s. He facilitated the technology transfer, and helped deliver three key areas of F1 engine thinking in the design of the 1.6 Energy dCi 130.

1: Square

Matching bore and stroke is loved by F1 engineers and is also present here. It allows large diameter valves to be used, which fill the combustion chambers more efficiently.

2: Water flow

Transverse water flow* is a common in F1. It means smaller water pumps can be used. Renault has combined it with a double water jacket, allowing a controlled flow of water can be focused solely on the hot zones – combustion chamber, injectors – and cools each cylinder equally.

As water is fed downstream of the water pump, it does not flow round the combustion cylinders, meaning the cylinder head is cooled more efficiently. Water flows ‘natrually’ round the system too, with no obstructions, meaning less wasted fuel.

3: Internal friction

Super-finished surfaces and UFLEX piston ring technology have both been used, after featuring in F1 for the past decade. UFLEX is, says Renault, like a multi-blade razor: it adapts to contours and does not exert undue pressure – maximum efficiency, minimum friction.

Low-pressure EGR

Most Exhaust Gas Recirculation systems are high pressure. They take exhaust gas from the combustion chamber almost as soon as it leaves, and inject this hot gas straight into the air intake. This reduces NOx but raises the intake pressure, restricting turbo pressure.

The 1.6 Energy dCi 130 has low-pressure EGR. This is far more complicated. Exhaust gases are recovered much further downstream, after they’ve been through both the turbine and particulate filter. They are cooled in an intercooler, then recirculated through the turbo to increase its pressure.

They are then cooled a second time, before re-entering the air intake. This ‘cold loop’ means the recirculation rate can be increased, further improving efficiency and reducing NOx levels.

Remember how turbocharged engines perform better on cold days, because the air density is higher? The same applies here.

The 1.6 Energy dCi 130 allows it because the distance between the catalyst, particulate filter and air intake is so short.

Thermal management

Cold engines – below 80deg C – are inefficient: combustion is incomplete and cold lubricant is more viscous, increasing friction.

Renault helps the engine warm up 3 minutes faster by using a valve in the cooling circuit. This is closed when it’s cold, so water can’t circulate through the engine, around the combustion chambers. The engine thus warms up faster. Water does, however, flow round the engine: that double jacket coming into play again.

When warm, the solenoid opens. And when it’s really warn, the thermostat opens, engaging the entire cooling circuit. The transverse flow of water is F1-derived and results in a simpler thermal management system that’s consistent and effective. A direct Renault F1 crossover to road cars.

Other stuff

• Renault claims swift variable-geometry turbo response from low revs, that’s so good, the technology behind it has been patented.
• The compression ratio is lower, for fewer emissions, with performance maintained by a higher turbo pressure: 2.7 bar is a 12% increase.
• Injection pressure is capped to 1600 bar, rather than 1800 bar, so smaller components can be used.
• The engine is the first to benefit from full work by Renault’s new NVH department: Renault says it’s as refined as a D-sector vehicle.
• 160 engineers worked on the engine, which took 32 months to complete. 76% new, the project cost €230m.
• Downsizing from 1.9 to 1.6 reduces the swept volume of each cylinder by 16%.

Although the Energy dCi 130 programme was co-funded by Alliance partner Nissan, Renault led development through being the ‘acknowledged diesel specialist’ of the two. Unlike Nissan, it was also able to call upon an in-house F1 programme, and it’s this learning that’s been applied here.

It’s easy to scoff at such claims of F1 technology transfer, but here, Renault given proof positive that race track learning really can benefit road cars – with 64.2mpg and 115g/km being a benefit all of us can enjoy.

Now, Renault, just bring on the Megane Coupe Lotus Energy dCi 130 launch special.

* Transverse water flow explained: Most engines use longitudinal coolant flow: it enters at one side of the cylinder head and flows through the entire head before exiting. See the problem? Yes – cylinder 1 heats up the coolant before it reaches cylinder 2, and so on. Poor cylinder 4.

Transverse flow sees coolant enter the side of the engine, with the return at the opposite side of the cylinder head. Each cylinder is separated from the others to avoid interference. Result? No heat soak from one cylinder to the next, making it much more efficient.

Longitudinal is commonplace, as it’s easier to cast and thus mass-produce. Transverse is better, though. In which direction does the coolant in your engine flow? Have you ever even considered it? I’m thinking not…

+ Nic Hamilton: in the family

+ SEAT + Germany = enjoyneering

+ Jason Plato: real-world racing car superstar

Lewis Hamilton’s brother Nicolas Hamilton starred in his first motor race last weekend – in the family tradition, on live TV.

Also in family tradition, he had a stellar first lap, with a great start and some tenacious diving-for-gaps earning him a good few places by the first corner. Remind you of anyone?

Nic Hamilton’s racing in the cut-and-thrust of Renault Clios. As an ardent fan of the championship, I wouldn’t wish it on any beginner – yet Nic lined up on Sunday for his first race, after just 3 months driving a race car.

Before then, it was Gran Turismo and Forza: like Nissan/PlayStation star Lucas Ordonez, Nic’s been turned into a real life racing driver courtesy of the finest coaching. Power to him, as well.

There’s a local interest for me here, though. See, over Christmas, I went jogging, on a slightly different route around the Wednesbury home of my girlfriend Tam. And what should I see, but the metallic grey trucks of Total Control Racing – complete with fluorescent orange ‘TCR’ logo bouncing off the snow I was pretty foolishly jogging upon.

I thus found out more: discovered they’re a team that competes (or has competed) in the Renault Clio Championship, Porsche Carrera Cup ,Ginetta G50 Cup and SEAT Leon Championship. Quite a role call.

And, now, I’ve also found out they’re running the boy Hamilton in the Clios this year. A chap down the road has even probably stuck on the Vodafone logos that caught the attentions of so many at Brands this weekend (not least big bro Lewis).

That’s quite cool. Hence, I’m going to find out more. I’m off to Donington next week, for both some BTCC action and a catch-up with the TCR boys.

More anon: for now, make sure you watch ITV4 next Sunday, for the latest in installment in the Hamilton racing dynasty.

+ The most amazing save of 2009

+ How fast would your car be with more power?

+ BMW LCI not ASAP for M

Conquest customers are every car maker’s dream buyer. Not only is it a sale for them, it’s a sale their rivals are not getting – a double win, of sorts.

Be warned though, if you’re a lifelong VW Group stalwart, who’s switched over to Renault after being seduced by the incredible damping development present in every recent model.

Because, you may just be unwittingly gifting thieves an open door.

Check out the image above: on the left, is a VW flip key. On the right is one of Renault’s new VW-mimicking flip keys, more satisfying than the eminently losable keycard, and more than up to VW build standards.

The same, then? No – and herein lies the risk for those unaware conquest Renault drivers.

Check out the other side of the VW key. Top button? Locks the car. After a day or so, you’ll be doing it by feel, without looking. The learned response muscles do so well, in action.

Compare, though, to the Renault key. Same feel, same trip of buttons, same location… but, no, not quite!

There, see, the top button UNLOCKS the car. If those muscles don’t relearn, then, reflexes will be gifting robbers the contents of your glovebox and more besides.

Customers will learn this, eventually, I guess. For motoring journos, though, it’s a different matter.

Cue airport car parks at launch time, dotted with Renaults offering easy pickings to fans of half-eaten Ginsters, fuel receipts and Starburst grab-bags.

Next event, I will be checking…

RENAULT and I won our class in last year’s MPG Marathon – a right ol’ result, it was, after 400 miles’ somewhat steady driving.

But how? All down to the Grand Scenic I drove – fitted with the 1.4-litre TCe ‘downsized’ engine.

In Renault parlance, this is a 2.0-litre power-puncher with 1.6-litre fuel-sipping ability. Tiny turbo, no direct injection, Nissan all-alloy block and plain efficiency. It’s a canny wee thing, alright.

Particularly if you want to drive economically. See, its key characteristic is delivering loads of torque at really low revs – diesel-like revs, in fact. Throughout the entire Marathon, I honestly didn’t exceed 2000rpm. And still managed to summit the 1-in-2 climbs dotted through the route.

That tiny turbo allows this; it spools up fast, which is just what you need for eco driving. Here’s traits I exploited:

•    Responsive to light throttles
•    Ability to select 6th at ridiculously low speeds
•    Linearity when modulating the throttle
•    Turbo doesn’t ‘run away’ from you
•    If you’re genteel, then so will it be

Being eco is about fluid motion. You need to swim along, with not a misplaced stroke, slipping along like an eel. Only with infintesimal control over the fuel being pumped into the engine can you do this.

Tiny turbo engines often produce great figures on the test rig, but plunge in real life, due to the turbo sucking in air like an iron fist, and forcing fuel injection to throw petrol in accordingly. Many people who drive at low revs and in a seemingly eco manner actually get mediocre economy – because of the lack of control the engine seems to have over itself.

None of that with the TCe. If you want to accurately throttle back as far as necessary to maintain pace, you can do. No torque-free gullies to fall into, no risk of being left floundering. It’s almost electric-like in its reponsiveness when you’re taking it steady.

The result of this is 50.3mpg in a 7-seat Grand Scenic. Official.

Wake up with the sun

Oil be: It’s back

RenaultSport past to inspire turbo future

SUNROOFS in cars have really fallen out of favour in recent times. Little wonder, now air con’s de rigueur.

But I had a revelation last week, that made me realise they still have their place – as lifesavers.

One test Renault Grand Scenic. Dynamique spec, with a few choice options, including the whizzy electric sunroof.

In the style of the Peugeot 205, this slides outside the vehicle, rather than inside, so looks super-cool on the move.

But, as well as popping ‘up and over’, it also tilts upwards, like the roof of every 1980s company car driver’s dreams. Tilting sunroof, at the turn of a knob rather than the crank of a handle. Majestic.

I did this, randomly, one morning. Know what happened? I immediately felt loads more awake. Why? Because all the stuffy air that was unknowingly rising within the cabin had an instant route to escape. There was now airflow in the Renault, from fresh in the vents, through me, and out the roof.

The carbon monoxide levels in the car plunged, I felt a million dollars and Renault had someone closer to justifying the heinous cost of electric sunroofs nowadays.

Far from being frozen out by air con, the sunroof still has a place – as a safety aid. Hot air rises. Here’s its escape route… meaning that bit less risk that it’ll be you relying on a lucky escape.

Of course, they probably knew all this in the 1980s already. Again: to learn, first you must look back…

Why Ford Econetics break the rules

Oil be: It’s back

RenaultSport past to inspire turbo future

TORQUE is all-important to the drivability of a car. if you want manic high-rev fun, you’ll get an S2000. Bags of bhp. No torque.

But if you want something that’s quick when you’re not, too, bag a Golf GTI. Decent power – but no shortage of Newton metres, either.

This was brought home by a drive in Renault’s Clio TCe. The 1.2-litre engine is lost in the bonnet, and it’s easy to miss the tiny turbo. But it’s this that turns it from languid to lugubrious.

The torque curves show why. Here, on the left, is the torque plot for the teeny 1.2. On the right is that for the teeny 1.2, plus turbo. The shape tells you what you need to know: on the left, it’s peaky. On the right, it’s flat.

For torque, peaky is bad. Flat is good. It means, with the TCE, you’ve got 135Nm NM from 1800 rpm – so it’s responsive in normal running. Has guts. At the same engine revs, the non-turbo is muscling out just 90Nm.

In other words, at the same engine speed, the TCe has 50 percent more muscle!

As most drivers both don’t like revving engines all the time, nor continually changing gear, this means that, everyday, the TCe is the more pleasant car. easier, punchier, more refined, nicer. Confirmed by a charge on the road; it’s a peach.

But this torquey profile made me realise that, actually, I could have garnered all this simply by looking at the torque curve. There was my evidence – merely confirmed by a test drive.

There’s something else, too. Weight. The Clio is a heavy car – 1080kg. So it needs a hefty slab of torque to counter this. A Peugeot 107? That’s got just 93 Nm of torque overall – but weighs just 800kg. So, doesn’t feel as torque-deficient as a Clio 1.2 non-turbo.

There’s a fair bit to all this – I’m looking forward to investigating more in the coming months.

Why Ford Econetics break the rules

Oil be: It’s back

RenaultSport past to inspire turbo future

MG nearly launched an SUV

ARONLINE has come up with a real gem – a prototype of an MG off-roader!

Based on the SsangYong Rexton, it shows the genius of Peter Stevens; his restyled bit, the front end, really is properly smart, I reckon.

It was to be called MG due to licensing issues over the Rover name, and would most certainly have enraged MG die-hards.

I, for one, can maybe see the merits, though – despite the mediocrity of the base vehicle. What sort of benefits could a tie-up with SsangYong have brought, for example? Yes, the firm’s been in trouble recently, but it also has a very promising new contemporary Qashqai rival waiting in the wings.

Imagine if MG Rover had been able to get in early on a co-development, Honda-style, with this? Coupled with a Fiat Stilo-based mid-range hatch, and perhaps a Renault Espace-derived people carrier? Even a tie-in with Lotus-owning Proton? We can but dream…

Twist-beam rear suspension is fundamentally flawed
My obsession over rear suspension on front-drive cars continues. You’ll no doubt be delighted to hear.

Latest view? That of a chassis suspension contact. His view is that twist-beam rears can never be as good as the far superior multi-link alternative.

This is because of two fundamentals. They lack lateral stiffness. And they allow the wheels to far too readily camber-steer when cornering. In journo-speak, this is the difference between and floppy and stiff rear end.

Tuning is still a massive part of how a car will turn out, he says. But the base multi-link engineers have to work from is that much better to start with, so they stand a better chance…

Fuel is going up
FUEL has risen by 2p a litre. With VAT, that’s 2.3p a litre. For the average tankful, it’s £1 a shot up.

One fuel retailer is trimming the rise for another week. But surely, as fuel has been bought in advance, they all should, until current stocks run out? One to watch.

Even so, I’m filling up today.

Saloons are dead in the UK
RENAULT for years went against the grain and offered saloon versions of its mid-range Megane.

Not anymore. It’s just revealed the tidy-looking Fluence, which is built in Turkey and based on the excellent current Megane platform.

But there are no plans to bring it into the UK. Proving that family buyers want family hatchbacks, not fuddy-duddy saloons.

When one of the market stalwarts leaves the sector, you know it’s now of minimal importance. Which is what makes it such a tragedy that Chevrolet’s fantastic Cruze is saloon-only.

Give this baby a hatch (for which there are no plans, given its world car status – what, with the rest of the world preferring saloons), and it could be the bargain-buy family hatch of choice.

Alas, we’ll never know. But at least it ensures there will remain a future contender for the Star In A Reasonably Priced Car.

Relax. It’s ESP

Why do people hate the Lotus Elan?

BMW Z4 chassis secrets

IN the olden days, ride quality used to be great on smooth roads.

Soft suspension, coupled with 70-profile tyres, meant it was like riding on space hopper. Rubbery absorption of all you don’t like.

Get the wheels encountering something more challenging, though – such as a rut, or a pothole, or a fag-end, and all holy hell would break loose. Your 1982 Ford Fiesta’s ride quality would show the finesse of stepping off a cliff. One minute it’s OK, the next, it’s having you check the suspension top mounts hadn’t blasted through the bonnet.

Slowly, cars became heavier. And people became less willing to see the side of their Fiestas sink to one side when they got in, because of the overtly-soft settings. Bottoming out when you had the shopping and the kids in the back wasn’t brilliant, either. With an increasing demand for less boast-like handling, so car suspension became stiffer.

For years, car makers puzzled with this. For a while, we had stiffer cars that were now pretty inept everywhere. There wasn’t even the comfort of a chance encounter with new tarmac to make you think it was any good. And, no sooner had they sorted it, when the next model became even heavier. Thus, so it went on.

Now, though, we’re reaching a plateau. Cars aren’t getting any heavier. And suspension dynamics genii have worked out how to make cars pleasing. This means we require a new judgment of what makes ride quality good.

In a few days, I’ll be putting this to the test in a new Renault Clio. See, a while back, I tried the then-new Clio III, and left it with the nuggets of a theory in my head. With the Clio 2009, I’ve another chance to theorise on this, and compare it to both my mum’s rolly old Renault 5, and my quasi-rolly 1993 Clio.

I’ll keep you posted.

Rover rides with NASA

BMW Z4 chassis secrets

Vauxhall gives new Astra suspension a twist