Motoring
BMW has made some minor changes to its i8 plug-in sports car, including styling tweaks, interior trim upgrades (with the latest touch-screen iDrive system), a battery boost and suspension modifications designed to give better wheel control.
But the biggest change is this: the addition of a roadster model.
Removing a roof equals compromise. What are you giving up in the roadster?
Fair question: there’s usually opportunity cost in open-top driving, in terms of weight and packaging.
The i8 is a tremendously strong car already thanks to its carbon fibre reinforced plastic (CFRP) construction, but it still gains 60kg in the transition from coupe to roadster. That adds 0.2 litres per 100km to fuel consumption and 0.2 seconds to the 0-100kmh time.
You also lose the (largely useless) rear seats to accommodate the folding roof, but you do gain a 92-litre storage compartment behind the front seats. The chairs have power/memory function and the roadster projects a light-logo on the ground when you unlock it.
Styling is subjective, but for our money the roadster looks every bit as good as (better than?) the coupe. Because the folding top is fabric, it’s compact and has the same profile as the hard top.
The roadster also retains the distinctive dihedral door openings of the coupe.
When you’re driving it do you smile or just feel EV-smug?
Well, they’re not mutually exclusive feelings. The i8 has always met sports-car expectations by being very quick and very entertaining – if not quite as engaging as some of BMW’s more traditional enthusiast models.
But you get a nimble chassis, all-wheel-drive traction and the kind of linear acceleration that has to be taken seriously.
In Sport mode there’s also a growly soundtrack that’s very satisfying, even though you know it’s electronically generated.
The genius of the i8 is that you can have the rowdy sports car when you want it, but it’s also a zero-emissions commuter at the touch of a button.
The roadster’s removable roof adds another layer (excuse the pun) to the experience.
The roof stows behind the rear seats in 15 seconds, at up to 50kmh, allowing you to hum along in the open air... in near-silence.
How electric is this thing really?
Unlike its i-brand sibling, the i3 city car, the i8 is only available as a plug-in hybrid electric vehicle (PHEV). That means it has a battery that can be recharged from an external source (making it a proper ‘‘EV’’ in Kiwi government parlance) and power it for short distances, but it retains a combustion engine that can work in partnership with the electric system.
It’s clever because the battery powers the front wheels and the mid-mounted three-cylinder turbopetrol engine powers the rear (each has its own transmission). Improvements to the lithium-ion batteries mean EV range has been extended in this updated i8 from the 37 kilometre of the pre-roadster generation to 55km in the new model. The battery can be recharged to 80 per cent in under three hours.
You can’t always take a claimed EV range too seriously in real world running, but we found a minimum of 40km was realistic in the i8 roadster – enough for a city commute (or even two) between charges.
You can select an ‘‘eDrive’’ mode and prioritise pure-electric, but if you run the i8 in Sport it actually uses the petrol engine plus regeneration to recharge the battery as you go – so that maximum boost is always available from both power sources for performance driving.
But you’d still much rather have the coupe, right?
Seriously, no. Like so many other much more expensive mid-engined machines, the i8 roadster loses nothing in terms of visual appeal, precious little in terms of performance and opens up a whole new level of enjoyment compared with its coupe sibling.
That’s assuming you can swallow the extra $23,200 the roadster costs over the fixed-roof version.
Any other cars to consider?
The combination of a plugpowertrain, exotic construction and that mid-engined supercar-like shape makes the i8 roadster unique for its $300k price.
However, quick reality check: for less money you could have a Porsche 911 Targa 4 GTS ($283,700), or pretty much any kind of 911 drop-top save the Turbo models. How about a Mercedes-AMG GT roadster for $269,500 or the Jaguar F-Type SVR convertible for $255,000?
One last thought: the Alfa Romeo 4C Spider is similarly styled, also has exotic carbon-fibre underpinnings and costs just $129,990.
Granted, we’re getting well away from the whole hi-tech, ecoexcellence concept of the i8 roadster here. But you have to put that price into context.