Cylinder Deactivation

[Justin Case]

With all these laws coming in on efficiency we can be glad of one thing. At least they made them in the first place

[Savage_M3]

Doesn't BMW or Mercedes employ cylinder deactivation on their V12's? I thought I read they they only use half the bank when cruising or idling. All 12 only kick in when accelerating.

[Law]

Originally Posted by IzzyGray

It's like that in Singapore; annual tax based on displacement. And since Singapore mimics a lot of British laws, this wouldn't surprise me.

Yup, Hong Kong does this as well, also a likely legacy of British institutions, though i'm sure it would've implemented similar taxes independently due to its small size & extreme urban density, much like Singapore.

In Mainland China, sales of cars are taxed based on displacement, not too sure about annual registration/license fees/road taxes but wouldn't be surprised at all.
Either way, cars are way cheaper in the States vs. the rest of the world, where import taxes, displacement taxes, and other burdens are placed on the consumer, many times resulting in 100% tax (essentially paying for the price of two cars).

This is why nouveau riche Chinese immigrants love coming to the US to buy high end cars; to them its a bargain!

[Dr. Stig]

The issue that makes cylinder deactivation not all that effective is that it only helps out when cruising on a flat or going downhill and as a result you're already getting (relatively) good fuel economy. The biggest fuel savings do not occur in this space because this is where relatively little fuel is being used. Think of going from 24mpg to 26mpg when cruising on flat or downhill terrain, you only increase fuel economy by 8%. Compare that to (hypothetically) if you could go from 10mpg to 12 mpg under acceleration or uphill, a 20% gain.

[sensi09]

One thing to mention is that cylinder deactivation needs a good amount of torque, so a s65 version would not work.

Oh and for the C7 a turbo v6 was considered, but they found they could get better mileage from a v8 with cylinder deactivation. Completely different way of thinking when compared to the e9x m3/m4

[SenorFunkyPants]

Here in the UK the annual car tax is currently (since 2001) based on C02 emissions.
The current M3 is in the top rate so thats 480 of our UK spondoolies (8 pigeons or a monkey down 20.)
On initial registration the tax is 1065 quid (142 badgers).

[Ezio]

Originally Posted by sensi09

.

Oh and for the C7 a turbo v6 was considered, but they found they could get better mileage from a v8 with cylinder deactivation. Completely different way of thinking when compared to the e9x m3/m4

anyone who thinks just because its a big V8 it has to get bad MPG hasn't taken a modern look at it.

trust me when i say i am not happy about the M4 going with these turbo I6 engines. after they gave us this race high revving V8.

but the sad truth is that the I6 engine coming in the M4 will be "socially" accepted to many people. as a corvette having a turbo V6 might not be as socially accepted. so there was for sure a push for a V8 in that car more so than the M4.