Z4 from $76,900 as BMW bins atmo six

BMW’S Z4 roadster will become the first model in Australia to come with the Bavarian brand’s new turbocharged 2.0-litre four-cylinder petrol engine when it arrives in November – with prices being slashed across the range by up to $9400.

The move signals the end of naturally aspirated engines in BMW’s compact sportscar, with the new N20 turbo unit – in two different states of tune – replacing the old straight-six sDrive23i and sDrive30i.

Despite lacking an evocative straight-six exhaust note, the new engine – which employs twin-scroll turbocharging, direct injection, variable camshaft timing and valve control – should keep everybody happy.

In 30i-replacing 28i guise it produces 180kW, which although 10kW down on its predecessor is compensated by a 40Nm increase in torque to 350Nm, enabling the 0-100km/h sprint to be dispatched in 5.7 seconds – a tenth quicker than before.

Even better, fuel consumption plunges 21 per cent to 6.7 litres per 100km and places the 28i into the government’s fuel-efficient category under Luxury Car Tax rules, resulting in its $89,400 price (before on-road costs) being $8700 less expensive than the car it replaces.

It is a similar story for the detuned 20i, which replaces the 2.5-litre unit of the outgoing 23i to create a new base model priced from $76,900 – undercutting the least expensive variant of the new Mercedes-Benz SLK by $6000 and representing a significant $9300 saving over its predecessor.

Peak power is 15kW down over the old 150kW unit but torque is up 20Nm and fuel consumption equals that of the 28i.

Equipment specification remains as before, except the new four-cylinder variants both feature regenerative braking and idle-stop is fitted with the standard six-speed manual transmission.

Four-pots also get the option of a new eight-speed automatic transmission with paddle-shift, which will be offered for $3500.

Although the two new four-cylinder Z4s will not hit local showrooms until November, BMW has also applied immediately-effective price cuts of $9400 to the sDrive35i and sDrive35is variants, which now come in at $107,500 and $120,500 respectively, bringing BMW’s fastest Z4 within the price realm of the Mercedes SLK350 ($118,900).

BMW sales are down 5.6 per cent this year, with 11,174 vehicles bearing the Munich marque leaving showrooms so far. Just 83 Z4s have been sold, down 60.3 per cent.

Sales should increase with the introduction of the new 1 Series next month and the new 3 Series volume-seller early next year.

The folding hard-top Z4 has averaged about 25 units per month since its May 2009 launch. Its high point was 50 sales in June 2010, with a low point of just five sales in July this year.

2011 BMW Z4 pricing:
sDrive20i	$76,900 (new)
sDrive20i (a)	$80,400 (new)
sDrive28i	$89,400 (new)
sDrive28i (a)	$92,900 (new)
sDrive35i	$107,500(-$9400)
sDrive35i (a)	$111,000 (-$9400)
sDrive35is (a)	$120,500 (-$9400)