Why has not auto world looked at digital technology?

What planet/century are you from?
Morst cars are full of digital technology, in fact most have too much rendering them complicated to the point of uselessness if you have the temerity to open the doors in the wrong order, or try to leave the car with the engine running in cold weather.
How do you think the engine mapping data is stored if not digitally? Maybe it's recorded as a pile of sticks of different length chucked into the boot?
Del
<slaps furry head with paw>

Kindly read my poser. IC engine itself should be made like a digital iC engine - with one cylinder capacity of say 100 CC, second of 200 CC. So that you can fire only 100 CC idling and up to say 20kmph, then 200 cc between 20kmph to 50 kmph and then both making it 300 CC for 50 kmph to say 60 or 80 kmph and so on.

I am not referring to audio system of fuel injection control system.

Ah - I noticed your dictionery does not include kmph (kilometer per hour) !!

...I suggest the title isn't appropriate and the post isn't concise.
But sorry if I offended.
Del

Fine- but I have no technique of changing the title now

FYI: http://en.wikipedia.org/wiki/Variable_displacement

Thank you very much. That sounds interesting!! I just down loaded- will read at leisure.

I'd not waste my time reading it. It might prejudice your out-of-the-box thinking.

Perhaps that explains why automotive imports from England have fallen off in the past decades. US auto manufactures long ago abandoned piles of sticks for engine mapping in favor of portable abacuses

I shall use what Dell said but in the way you understood your question:

There are already engines running on more or less cylinders according to power needs.

So that your idea was even by automotive experts already implemented.

It was not so much used before the valves could have a direct electromagnetic individual control. The problem was solved with special solenoids designs which are still quite expensive and as available as mechanical controls.

I don't know how to break the bad news, but this has been tried . . . as early as 1905. Sturdevant did it. Enger did it in the 1910s. Then, there was the old "hit-and-miss" engines.

Electronics play an important role in automobile of today. Cutting off or adding cylinders to compensate for required power has been tried, but the gains in efficiency were negligible compared to complications. The electronics are used successfully in providing complex ignition advance angle in function of engine speed and load.

It could be used to locate properly the engine working point on Optimum Efficiency Curve (OEC) at all time depending of Opening of the Throttle (OT) [load] and the Driving Resistances Curve (DRC), which is also dependant on transmission ratio. The adequate algorithms come to play an important role here. When opening throttle to get the required power, we need to adjust the transmission ratio to get the intersection of DRC curve and OT curve at the point of the OEC. This is where we realise the optimum fuel consumption. This can be obtained only with Continually Variable Transmissions (CVTs). Using discrete ratios transmissions (conventional ATs or MTs) we do not have the possibility to fully exploit the Engine Performance Map (EPM). We have to jump from one ratio to next, with no ratio in between.

The electronics have an important role to play here to [properly] manage the engine and CVTs according to varying road resistance conditions and power (speed) demanded by the driver.

bet he has a prius in the driveway next to his Edsel

Not at all. Hybrids make little sense, two systems, high cost, with small gains in efficiency in the city driving, and not at all in highway driving. Future lies in truly efficient vehicles, ultralight, super-aerodynamic, with ICE efficient engine and CVPST (power split CVTs), - which will be [eventually] converted to EV. The Prius gains in efficiency, come from its good drag coefficient Cd=0.26... when other cars to which Prius is compared have Cd=0.4 or more... The medias compare apples to oranges...