It's 2004 and I just drove a Honda Insight for the first time.
It's about time.
The Insight drove exactly as I imagined-like an old CRX HF with a loose vacuum line that makes it stall when you come to a stop. The only real surprise is that it seamlessly starts running again as soon as you need it to.
The Insight itself is old news, but it got me thinking. It's common knowledge, among those of us who know the future, that within a decade hybrid drivetrains will be so common marketing departments will stop bothering to brag about them. Like variable valve timing, ABS, power brakes and automatic transmissions, this amazing new technology will soon blend into the dull fabric of daily life like just another stain of progress.
Clones of both Toyota's parallel Hybrid Synergy Drive and Honda's series Integrated Motor Assist (IMA) will be everywhere, but only the progeny of Honda's system will ever earn more than a curious mention in these pages. The reason is simple. Toyota's parallel system has to take input from the "gas" pedal and turn it into electric power, gas power, or a combination of both, and make it all feel the same. This can only be done with substantial computer interference and some sort of automatic transmission, both of which suck the fun out of any car.
While the Toyota system adds layers of complexity, Honda's IMA system strips them away, removing the alternator, its mounting bracket, belt and tensioner, eliminating the starter motor, and adding only a fancy flywheel, one more computer, and a few hundred D-cell batteries. There's nothing inherently complex about the IMA system, it simply takes something that was already spinning-the flywheel-and sticks some magnets and coils of wire on it to make it into a motor/generator. Stepping on the gas always gives you gas power; sometimes it gives some electric power, too.
Despite the fact that it currently powers only eco-appliances, a hybrid drivetrain isn't necessarily a ticket to snoozeville. IMA does four good things that we like. In Insight trim, IMA is capable of sending an extra 15 hp to the wheels. Extra power is good. IMA can use engine braking to charge the batteries, eliminating the need to do it while accelerating. That effectively frees more power, which is still good. Third, IMA can use that 15 hp to spin the engine up to idle speed before firing the injectors, replacing the universal crank-crank-fire routine with a more mysterious one, where the engine suddenly goes from not running to running with no perceptible transition. That saves gas by allowing the engine to turn off whenever the car is stationary, and since that gas can be used to make power later, it is, in a way, making more power, which continues to be good. Finally, IMA works better with manual transmissions than with conventional automatics. Score one for our side.
The only reason IMA is seen as an eco-groovy powertrain is that it can be used to prop up an otherwise gutless engine, adding 15 hp that it gathers from wasted engine braking power rather than from fuel. Combine gutless with free power and you have incredible efficiency. But wait, power is power, no matter what you put it in, so why not put those 15 hp in something fun?
Simple. Because the marketing department hasn't asked for it. IMA is more expensive than just making 15 more horsepower out of gas, so it's easier to sell a sports car if you just bore bigger holes in your engine. There are few companies with the balls to make product decisions based on engineering sense before obvious marketability. Few, but not none.
Anyone remember the Miller cycle engine? Ever heard of a Wankel rotary? Anyone asking for a four-door sports car? Remember what a crazy idea the Miata once seemed? Mazda will do it. Mazda will do anything.
The RX-8's new side-exhaust RENESIS rotary engine is a vast improvement over the old peripheral-exhaust 13Bs, but it still has a few weak points, most of which, it turns out, would be cured by a little IMA. In spite of its reduced overlap and better low-rpm breathing, the RENESIS is still a little weak at low rpm. An electric motor makes as much torque at zero rpm as it does at its maximum speed, so it can be a big help at low rpm without compromising high-rpm performance, something few other power boosters can claim.
The RENESIS also continues to be a little thirsty, so turning off instead of idling and using a little battery power to reduce the use of gas here and there can't hurt. Rotaries are also a little difficult to start. While much improved with the side exhaust ports, it can still take a few tries to restart a hot RENESIS. Spinning the engine to full idle speed before ever firing a fuel injector ensures the engine will be going fast enough to make good compression and virtually guarantees that not a single chamberful of gas will get through without igniting.
In addition to that little starting trick, IMA can help emissions and driveability in surprising ways. Getting a crisp response to a sudden jab of the throttle requires a brief shot of rich fuel mixture. Try avoiding this in the name of low emissions, as Toyota seemed to with the Celica GT-S, and you end up with a frustrating stumble when you upshift and strangely dissatisfying throttle response the rest of the time. With IMA though, you could keep it lean and power through that stumble with a shot from the electric motor.
There are two big engineering problems with IMA in a sports car. The first, of course, is weight. The motor itself adds little compared to the alternator and starter it's replacing. It also sits at the back of the engine, which helps shift the car's weight distribution more toward the center. The batteries, however, must weigh something. In the Insight, the battery pack is an array of 120 very special D-cell batteries and the whole system (motor, controller and batteries) adds 150 to 200 pounds. Mazda engineers throw a toga party whenever they figure out how to take that much weight out of a car, so convincing them to put it back in would be tough. Being a bunch of D cells, though, it could be put wherever it's least dynamically offensive, like under the seats, in the transmission tunnel, or lining the carpet.
The other hurdle is keeping them charged. In a city car, there's plenty of coasting and braking to charge the battery with, but take an RX-8 to the track or out in the mountains and there's trouble. With far more time spent on the throttle than off, you'll constantly be asking for IMA power, but seldom giving it back. Keeping power delivery consistent would probably mean saving the electric power boost for low-rpm use where it makes the most difference anyway, and where it won't be drained the second you hit the track.
Clearly these two little problems aren't enough to keep Mazda from being interested. Mazda recently hinted at the shape of the third-generation Miata with the Ibuki concept at the Tokyo Motor Show, which happened to be powered by a 1.6-liter four with a clone of the IMA system. The question of an electrically assisted rotary isn't if, it's when. How long will it take for IMA to be cheap enough to stick in a car when marketing doesn't ask for it?