Porsche 718 vs BMW Alpina B4

What's the difference?

If this is to be the end of the 718 as we know it, then it is an end to be remembered. Porsche has produced something special in the Spyder RS, a sports car that can compete with the 911 on any stretch of road - which is something so few cars can claim. The focus on performance has driven the entire concept of the car, but all the elements work in harmony, with form and function coming together.

You could almost call the B4 S the anti-M4. It's still fast and practical but from a completely different perspective. It's much more a grand tourer than the M4 and even with the Akrapovic exhaust (usually a byword for joyous, anti-social racket), subtle.

For some, the price won't matter because the Alpina delivers what they want - M4-like straight line performance without the histrionics or the uncompromising chassis. And there's also a bit of that perverse exclusivity of the styling that you won't get anywhere else.

As the pinnacle of not only the current 718 range, but potentially the entire combustion engine era of the Boxster, Porsche has pulled out all the stops for the Spyder RS.

This includes major changes to the design, but none are purely for aesthetic reasons and instead are driven by the search for performance; and the fact they make the 718 look tougher, meaner and more purposeful than ever before is just a bonus.

It’s a comprehensive redesign that starts at the bumper with a new front lip spoiler to enhance downforce. Then there’s a pair of NACA ducts on the lightweight bonnet to improve brake cooling without compromising aerodynamic drag. The lightweight front fenders include wheel arch vents to stop any potential for front-end lift at high speeds.

And the fenders aren’t the only component that’s gone on a diet, there’s a lighter exhaust, lighter wheels, lighter bonnet, lighter roof, lighter door panels and even lighter carpets on the inside. All up, the Spyder RS tips the scales at 1400kg, which is 40kg lighter than a standard 718 Boxster.

If it’s still not light enough, you can opt for the optional 'Weissach Package' (which was fitted to our test car), which brings even lighter 20-inch forged magnesium wheels and carbon-fibre reinforced plastic for a range of parts including the front luggage compartment, rollover bars and ducktail spoiler on the Gurney flap – plus some cosmetic enhancements.

And we still haven’t even touched on the biggest design change yet - the rear half of the car. Starting with the roof, which Porsche actually calls a ‘sunshield’ and ‘weather guard’ because it’s a stripped down version of what the brand usually uses, to save weight and let the glorious engine noise into the cabin uninterrupted.

But it’s also necessary because the entire rear engine cover has been redesigned to accommodate the larger engine that Porsche has installed in the Spyder RS, a 4.0-litre six-cylinder instead of the usual turbocharged four-cylinder ‘boxer’ engines.

While the Spyder RS looks great with the roof/sunshield on or off, frankly the removal process is much too complicated and requires repeated viewings of a YouTube tutorial to still get it wrong.

While owners will (likely) eventually get the hang of it, it will always be a clunky and awkward process and that’s just the price of being so focused on performance, which you can accept or not.

Inside that ethos of performance over practicality continues, with sports seats, an Alcantara-wrapped steering wheel and even the previously mentioned lightweight carpet floor mats.

It’s a purposeful, rather than luxurious, cabin, but that perfectly suits the nature of the Spyder RS. Our test drive included several long stretches behind the wheel and at no stage did it feel uncomfortable or impractical, despite its stripped-down design.

Alpina has always had a particular aesthetic that could uncharitably be termed as mid-'80s West German - all set square angles and body graphics. Think David Hasselhoff's Berlin Wall look. The company has never really deviated from adding squared-off body bits to the various BMWs it has rebadged under its long-running agreement.

For the B4S, Alpina adds the signature billion-spoke alloy wheels (only a slight exaggeration), a new front splitter complete with Alpina lettering, a weirdly proportioned boot lid lip spoiler and - not even joking - pinstripes. Like I said, mid-'80s West German. You can still recognise the sleek 4 Series Coupe but perhaps the worst of it is the super-sized, wonky-looking ALPINA B4S on the boot.

Inside is rather more restrained apart from the ill-fitting Alpina plaque under the climate control. Again, it's all 4 Series in here, with the lovely Merino leather liberally applied across the cabin. Less lovely is the wood on the door pulls and console but the door cards have an oddly appealing woven leather which looks and feels good.

Sadly the standard 4 Series steering wheel is along for the ride. There's nothing wrong with it - although the Alpina logo does look out of place - but if I were a product planner, I'd beg for the lovelier M wheel.

One area where the 718 range is starting to show its age quite dramatically is the in-car technology. While Porsche’s native system is relatively user-friendly, the lack of wireless Apple CarPlay or Android Auto in any capacity is deeply out-dated; and was frustrating for this Android using reviewer.

Given the age of the current 718 platform, and the impending arrival of the new model, it’s understandable that the multimedia system didn’t get an overhaul, but for a $350K car it does feel a bit behind the times.

In practical terms the Spyder RS is a bit of a struggle if you plan to go away with it. We managed to get a small suitcase and backpack in the under bonnet storage, but that was at capacity. While the addition of the larger engine removes any meaningful rear storage space.

If you're in the front, you're in luck - it's a comfortable place to be, with plenty of leg and headroom. Down back isn't terrible despite the coupe roofline. The two seats are nicely shaped for maximum comfort and separated by an odd plastic tray. The fold-down armrest has two cupholders.

Front seat passengers score a pair of cupholders (bring the total to four for the car) and the long doors will hold a bottle each.

The boot swallows a reasonable 445 litres, which isn't at all bad.

If you thought BMW don't mess about when pricing up its cars, you best strap yourself in. The 440i-based B4S starts at a solid $149,900. That's $48,000 more than the 440i and significantly more than an M4 Pure. But there's plenty of gear on offer and some genuine, bespoke Alpina additions.

Standard are 20-inch signature Alpina alloys, 16-speaker harmon kardon-branded stereo with DAB, super-soft Merino leather everywhere, dual-zone climate control, around-view cameras, reversing camera, sat nav, keyless entry and start, front and rear parking sensors, active cruise control, heated and electric front seats, head-up display, auto headlights and active LED headlights, LED taillights and electric sunroof.

The stereo and sat nav are run by BMW's iDrive. It's a cracker of a system and almost gets away without Apple CarPlay and Android Auto. The absence of such simple pleasures at this price point is a bit lame, but here we are.

The key stat for the engine is the cylinder count. Gone are the four cylinders and instead it’s a return to Porsche’s iconic flat-six.

Specifically, the same 4.0-litre six that Porsche uses in its 911 GT3, which is a lot of engine to squeeze into the middle of this lightened sports convertible.

In order to keep the 718 in its place (beneath the 911), Porsche has slightly detuned the engine, so it makes 368kW/450Nm (compared to 375kW/460Nm in the 911 GT3), but the German brand has never worried about a kilowatt contest and instead prefers to focus on driveability and the other elements that make a drive great.

To that end the combination of air-intakes next to the headrests and the lightweight stainless steel exhaust (which gets titanium tips on the Weissach Package) helps the Spyder RS sound like a Carrera Cup racing car when you really wind it up to its 9000rpm redline.

Not that the performance isn’t spectacular, though, with Porsche claiming it takes the Spyder RS just 3.4 seconds to run 0-100km/h, only 10.9 seconds to get from 0-200km/h and will hit a top speed of 308km/h.

The engine is paired to a seven-speed dual-clutch auto transmission (or PDK in Porsche-speak) that the company claims has “short-ratios”, but with peak power not hitting until 8400rpm and peak torque from 6750rpm, you don’t have to rush the ratio changes.

A lot of your extra money turns up under the bonnet. These days the 440i packs BMW's slick B58 turbo straight six and the B4S does likewise. The boys from Buchloe in Bavaria (there are certain to be women there, too, I just liked the alliteration) added a pair of Alpina-spec turbos to generate a whopping 324kW and, more importantly, 660Nm. Alpina says 600Nm (the max torque figure of the brilliant M4 CS) is available from 2000-5000rpm, while the full 660Nm is available from 3000 to 4500rpm.

The M4 Pure has 317kW and 550Nm from the S55 straight-six. Just so you know.

Like the 440i but unlike the M4, the B4S employs the dependably brilliant eight-speed ZF automatic found throughout the BMW range.

Porsche says the 4.0-litre engine in the Spyder RS uses 13.0L/100km, which is a big number for what is a relatively small car. But that engine is highly-tuned and built for performance not efficiency, so it’s something owners will need to accept.

Our test drive included some long highway stretches, as well as some spirited driving and urban commuting, so a good mix across all conditions, and we saw consistent returns around the 15-16L/100km range.

It has a 64-litre tank, which means a theoretical driving range of around 490km, assuming you can hit the official claim.

Alpina quotes 7.9L/100km on the combined cycle and we went through the premium unleaded at the rate of 11.7L/100km. I enjoyed myself, so that's not a terrible result.

I’m only giving it a nine out of 10 because perfection is hard for any car to achieve, but the 718 Spyder RS goes as close as any car I’ve driven. This is a masterpiece of modern sports car design, pushing the 718 closer to the 911 than ever before, which is something Porsche has clearly tried to avoid so as to not tarnish the image of its flagship.

But with the 911’s 4.0-litre flat-six in the middle of the 718, plus its more compact dimensions, the lightweight nature of the Spyder RS and the raft of chassis and handling enhancements, this really does leave you questioning ‘do I really need a 911?’

The steering is fantastically direct, the chassis responds to every input with precision and feedback and the braking is strong and consistent. Which helps because that engine is so good it launches you with ferocity and a glorious noise (as good as anything on the market today) whenever you squeeze down on the accelerator.

The highest praise I can give the Spyder RS is not that it was a dream to drive on winding, challenging roads, but that it was just as enjoyable on a trip to the shops or cruising down the freeway. Any drive in this car is a genuine pleasure.

One of the key differences between the B4 and M4 is the ride. While the M4 can crash over bumps and generally be a little hard to live with, the crew in Buchloe have gone after a much more plush ride. And in that they have succeeded because the B4 S is a mighty fine cruiser. Bumps are dismissed with a haughty disdain, even Sport + silliness doesn't completely write-off ride quality.

Very impressive too, is the steering. While still not at Lotus Elise levels of feel (few cars are), the Alpina tweaks connect the your palms to the road with more clarity than what you'll find in the 440i or M4. Where the M4 particularly adds too much weight, the 440i is a bit more circumspect in that regard.

And then we come to the engine. The B58 six is a belter, better even than the N55 that preceded it. It's still a 3.0-litre straight six but is part of BMW's modular engine family that starts with a 1.5-litre triple in the Mini and 1 Series. The Alpina-spec turbos are noisier, the Akrapovic exhaust lighter and also noisier. It doesn't have the all-out crackle and pop of an Audi or Merc (perish the thought), but when you're on it, the B4 means business. The 660Nm of torque, available over a wide rev range, delivers a steel fist wrapped in a velvet glove and bubble wrap - the speed builds rapidly but smoothly. 

The approach to the chassis tune seems to be based on the driving talents of mere mortals on normal roads, which is kind of like the 440i. It's terrific fun to drive hard but it's very forgiving and patient. The great thing about it is that you wouldn't think twice about jumping in it for the long haul, so comfortable and quiet is the cabin. The M4 will leave it for dead on a winding road, but that's perfectly fine.

One irritant is the replacement of the admittedly cheap BMW gearshift paddles with weirdly non-tactile buttons. They're not particularly easy to use and, probably worse for a sporty car, unsatisfying. It's an odd detail with which to go off the reservation. Cheeringly, the eight-speed ZF is its usual perfect self, so you don't have to worry too much about manual mode or go old school and use the shifter.

The Alpina ships with six airbags, ABS, stability and traction controls, ABS, stability and traction controls, forward collision warning, forward AEB, road sign recognition and active cruise control.

There are also two ISOFIX points in the rear. Neither the Alpina nor the 4 Series has an ANCAP safety rating.

It’s difficult to give the Spyder RS a clear score here because Porsche is cagey on the details. The public dealer websites indicate annual oil maintenance is required, with additional servicing every two years or 15,000km. 

How much that will cost is unclear, as despite the rest of the 718 range having publicly available prices, there were no such details for the Spyder RS (or even its Cayman sibling, the GT4 RS).

For reference, the 'standard' 718 requires oil maintenance ($895) for the first annual service and an inspection ($1500) the year after. Those costs continue to alternate annually out to eight years/120,000km.

Alpina offers a two-year/unlimited-kilometre warranty which is a bit behind the times and not in keeping with the price point. Servicing is another matter altogether and you're subject to your dealer's standard charges for servicing.