VTEC was especially fun in the old implementations, like the 4th gen Preludes. It was like someone lit off a booster rocket. Total blast to play with.
The lo/hi switchover is much smoother now, which I suppose is more refined, but it’s a lot less fun.
Variable valve timing dates back at least to 1849, when George Henry Corliss invented a steam engine that throttled by varying the shutoff points of the inlet valves instead of just restricting the steam flow to the engine with a valve.
I wonder if it is time for a steam engine revolution.
I believe the next revolution will be EVs. I predict that in 15-20 years roughly 40% of the new car offerings will be EVs, 50% will be hybrids, and the balance will be gasoline. However, seeing that even Ferrari and other hypercars are going to hybrid systems, my estimate on gas engines may even be too high.
Remember too that even with steam a fuel is needed to feed the fire to heat the water.
Yeah, it’s hard to predict but I wouldn’t at all be surprised if more than 40% of new cars are electric in 20 years.
All it’s gonna take to drive people to want electrics even more is another round of skyrocketing gas prices.
Or perhaps a revolution in battery array technology that brings the cost way down. While I can’t imagine what such a revolution might be, now that EVs are becoming a real market, I wouldn’t be surprised to see some such technological advances in the not-too-distant future. Demand in a new market often drives such things. Or perhaps I’m just overly optimistic about the future of EVs. 
Well, there was this Model 3 teardown article which gives the impression that if Musk can humble-up and learn a few lessons from long-standing automakers, Tesla will succeed. And the same article talks about the battery technology they have now, which the CEO of the company that tore it down said was shockingly advanced, and elsewhere he noted that no one else is even close to them in battery tech.
So if Tesla survives and continues to innovate on the battery front, that revolution might just happen.
I don’t foresee steam as a viable engine for cars. Modern steam power plants can achieve remarkable thermodynamic efficiencies, but in order to do so requires complete heat flow management. Running boilers above the critical temperature of water, and then superheating the steam even more, and then sending the steam through a reheater after every expansion stage of the turbine, finally condensing the steam at as low a temperature as possible in order to have a very low pressure at the turbine’s outlet, this requires acres of surface area and preferably a large body of water to cool the condenser.
If there is any hope for a Rankine cycle engine in a car, it would be at the bottom end of a combined cycle, converting some of the waste heat from the internal combustion engine’s exhaust into energy, possibly charging batteries in a hybrid car.
A lot of modern power plants are using Brayton-Rankine combined cycles. A gas turbine burning the fuel and providing power while the turbine’s exhaust fires the boiler of a steam plant providing additional power.