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Originally Posted by Heihetech
No! Something you have posted belongs to 30+ years old traditional cylinder
deactivation, nothing new, just the VW product is new. How much would you
expect to pay for such outdated technology?
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Why would you call it outdated technology ?
There aren't or weren't many cars with this feature - certainly not in its displacement range.
It goes well beyond switching off injectors while keeping the rest of the engine operating normally and calling the result an air-hybrid.
VW could have done that in the blink of an eye.
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You must pay some $16,000, or $2000 to trade-in your used car to get it, not cheap.
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The rest of the car will also be new
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Technically, it's 50% deactivation is the number that always trend to over-
deactivation, making engine power too weak to do regular driving.
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Apparently, it works just fine with half the cylinders out of action.
1250-4000 rpm is in the pretty useful range, and 100 Nm torque should be enough to accelerate a compact car when you're not pushing it.
It effectively turns the 1.4L into a tiny 0.7L engine, which should be powerful enough to keep the compact car rolling.
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Does it deactivate 25%???
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No.
Doe we need that ?
The savings would be less, and imbalance could occur - though VW has plenty of expertise with triples .
The range where 25% deactivation would be useful is likely pretty small.
When accelerating swiftly, it'll need all four pots.
Cruising, it only needs 2 to sustain speed.
When and how long would it need to use 3 cylinders ?
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Does it deactivate every cylinder alternatively??? NO! It only shut down 2 fixed inner cylinders, making them over cooled and suffering abnormal wear
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The 2 inner pots also run the hottest in normal operation.
I'm pretty sure this is what VW came up with after thorough research into the mechanical and thermal stresses of different possible configurations for cylinder deactivation - they've got to warranty it for a couple of years.