The internal combustion engine, for all its faults, is perhaps the one item in the automobile that best defines a company's values and engineering prowess as well as gives a brand much of its identity. For most automakers, the real estate under the hood is sacred territory, and with few exceptions, it's owned by the company that makes the car. And for good reason.

Would a BMW powered by a Toyota engine be as coveted among performance car enthusiasts? Would a Lamborghini with a Honda engine provide the same visceral experience?

Engines have mattered for this reason since the dawn of the auto industry. But that might change in the electrification era. Will anyone care who makes the electric motor so long as it delivers torque and range? This is one issue automakers are going to have to sort out in the coming years. I know they are already thinking about it.

In a recent report, WardsAuto examined the electrification plans of global automakers and found that the number of nameplates of battery-powered vehicles will increase from 14 this year to 85 by 2025. Sales projections are all over the map, from a low of 10 percent of industry volume to as much as 50 percent by 2030, according to various studies I reviewed.

Even at the low end, that's still 7.9 million electric motors per year (based on last year's global sales). I've been asking powertrain executives in the auto industry if bringing electric motor production in-house is being considered. The implications of that are huge.

Electric motors are smaller and have far fewer parts than internal combustion engines. So, building electric motors will require a new manufacturing footprint vs. today's engine plants. And because manufacturing electric motors is an area of expertise that automakers are not proficient in, workers will have to be retrained -- if automakers decide they need to build their own motors.

And that's a big if, says Brett Smith, assistant director of the manufacturing, engineering and technology group at the Center for Automotive Research, or CAR. Each year at the group's Management Briefing Seminars in Traverse City, Mich., an industry conference, Smith chairs a panel of powertrain executives. Of electric motors, he says:

"The engine you can tune to make it unique. BMW's tag line for many years was 'the ultimate driving machine.' And BMW's engine made that the case. The motor doesn't. What makes people care is the software that controls it. With electric motors, automakers are focusing more on the differentiation being more in the software, in the ability to integrate and bring the whole package together."

At least initially, Smith doesn't see automakers tooling up to produce electric motors in high volume. He says there are many motor suppliers that automakers can bargain with to get the best prices. "The question becomes, can automakers get economies of scale in manufacturing, and can they get that scale that differentiates them enough from the competition?"

For those of us who love to drive, the transition from gasoline to electricity will cause us to re-evaluate much of what we like about cars. For me, it's partially the mechanical sounds a vehicle makes that help me determine if I like it. Too quiet is no good. And harsh noises are also a turnoff. But a nicely tuned exhaust note, the whine of a supercharger and the sound of an engine ingesting air help make driving fun.

Smith sees the software that controls the electric propulsion system as a key area where automakers will help define a vehicle's character. "It's no longer sound or the [makeup of the] valvetrain. It's a very different principle," Smith says.

I've driven the Chevrolet Bolt, two of the three Tesla models and a Nissan Leaf. Technically, they are all excellent. But I don't know if I can bond with 'em the same way I could a Chevrolet Corvette, Nissan GT-R, Dodge Challenger or Ford Mustang.