Thursday 25th May 2006

BMW plots new supercar

The Z6: lighter, greener and a tech showcase

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Z8: more of a California cruiser

BMW plans an eco-friendly supercar to replace the low volume Z8.

According to this week's Autocar magazine, the new Z6 will be more focused, lighter and greener than its predecessor, and will belly up to the Merc SL and the Ferrari F430. It's alleged to be more than just a follow-up to the Z8 though, as volumes are expected to be higher. BMW hopes to make some 15,000 a year, compared to the total of almost 6,000 during the four-year lifespan of the Z8.

Flame-surfaced, it looks in outline like a cross between the Nissan 350Z and a bulky 911. it'll be around the same size as a 6-Series -- some of whose parts it'll use -- although it'll be more of a sports car than a the 6-Series GT.

It's front-engined and could be powered by a turbocharged V8 or straight six. It'll use an aluminium spaceframe chassis, with the whole thing weighing under 1,500Kg.

The Z6 is designed to showcase BMW's advanced technologies in the weight- and fuel-saving areas, so it may well get a carbon-fibre skin, along with extensive use of exotic materials such as magnesium.

Autocar suggests that the technologies deployed in the Z6 are likely to trickle down into lesser models over the next 10 years, including the next 3-Series. These include controlled air-flaps for improved cooling management, smaller, more powerful turbocharged engines with cam-less valvetrains, hybrid transmissions, foam cores, and sensors.

[Andrew D]

The Article said:

It's front-engined and could be powered by a turbocharged V8 or straight six.

Hmmm, to rival an F430 it'll need at least 400bhp, which rules out a straight six. The new M3's V8 will be good for 400bhp, but I can't see that going into a non-M car, and I can't see BMW developing a blown V8 with the same power as the M3's unit.

Aha! The twelve from the 7-Series! Brilliant! That's the one.

[dannylt]

Why does 400bhp rule of a straight-6? Given the NA one easily does 350+, just a small amount of boost would give 400+. Probably just a boosted version of the twin turbo 335 engine would do it, and be very light.

[Andrew D]

Well the S54 (E46 M3, Z4M) does give 343bhp, but not easily. In fact it's right at the limit, that's why it was only 20bhp more than the S52 in the previous M3. It's also why they kept going bang to start with and why the price of M warranties has gone through the roof.

Even with a ground-up new design, 3.5 litre is about as big as you can go on a straight six before the cylinders become too large for efficient combustion, and even heavily turbocharged to 100bhp/litre, that's still only 350bhp. And why would they go to that trouble when the 6-Series chassis already has form for taking a 370bhp V8 in the 650i?

[Zod]

They are hardly going to build a supercar slower than the M5 and M6.

[Andrew D]

Nodoubt there would be a Z6M with the V10, but if they wanted a range of them I'd guess there would be some with less power.