More Than Horsepower In The Honda CR-Z

In Translogic episode 6.4, we took a look at the new 2011 Honda CR-Z to see how it fits in with a few of Honda's benchmark vehicles from the recent past, the original Honda Insight hybrid and the S2000 roadster. In a way, the CR-Z is a blending of both cars. Honda calls the CR-Z a sporty hybrid, but given its 122 hp, that sounds like wishful thinking. However, horsepower alone won't tell us all there is to know about the CR-Z. Sure, it's fun to quote horsepower figures, but they don't mean anything unless you know how much the vehicle weighs.

For example, a Caterpillar 797F earthmover has a 20-cylinder engine that makes 4,000 horsepower but even a kid knows the earthmover isn't fast because it's heavy. If weight plays a role in taming the Caterpillar's 4,000 hp engine then it certainly has an effect on the average passenger car.

Automakers, racing teams and sports car enthusiasts know this as power-to-weight ratio. This is just a scientific way of describing how many pounds one horsepower has to move. The fewer pounds each horsepower has to move, the quicker the car will be, no matter what the horsepower rating.

The S2000's 2.2-liter, four-cylinder engine made 237 hp by the time it went out of production last year. While this is not a huge number by itself, consider the fact that the S2000 weighs less than 3,000 lbs and suddenly 237 hp sounds like plenty of fun. Each single horsepower of a base Honda S2000 has 12.1 pounds to move so the power to weight ratio is 1:12.1. On the other hand, a Dodge Charger SRT-8 with its 6.1-liter V8 nearly doubles the S2000's horsepower and although it does have a more favorable power to weight ratio, it's not nearly as big a gap as you'd expect. Every one horsepower of the Dodge's V8 engine has 9.8 pounds to move, for a power to weight ratio of 1:9.8.

But there's another point of consideration in a sports car, with a lower curb weight comes improvements in handling and braking. This is just simple physics, as it takes less effort to control or stop a smaller mass than a larger one. So the Honda's lower weight means it's also more manageable when turning the steering wheel or stomping on the brake pedal.

So what does this have to do with the Honda CR-Z? Well, the CR-Z weighs in at just over 2,600 lbs, so each of its 122 horsepower has to move 21.6 pounds. That's not so great compared to the S2000, explaining why the CR-Z is a fuel sipper first and a sporty car second. Honda clearly sacrificed quick acceleration in favor of more miles per gallon. But compared to the original Insight, which had to move more than 30 lbs with each and every one of its 73 hp, the CR-Z might as well be race car. Even compared to the current Honda Insight (1:27.8 lbs) or Toyota Prius (1:22.7 lbs), it's clear why Honda is pushing the CR-Z as a sporty car, as its power-to-weight ratio is clearly superior.

There's also the issue of torque to think about. Since the electric assist motor in the CR-Z can provide its peak 58 lb-ft of torque at 1,000 rpm, it gives the CR-Z quite a boost of off-the-line grunt. Electric motors are capable of delivering almost all their torque output immediately, which complements the relatively small 1.5-liter four-cylinder gasoline engine in the CR-Z nicely. When Motor Trend tested the CR-Z, it did 0-60 miles per hour in 8.3 seconds, which is

So the idea that the Honda CR-Z falls somewhere in between a hyper-miler's dream and true sports car is accurate. Honda adds a little fun by giving the CR-Z a six-speed manual transmission and is quick to point out that it's the only hybrid currently available with a manual transmission. However, Honda hinted that the 2012 Civic hybrid might have a six-speed manual as well.

The aluminum-bodied, first generation Honda Insight and Honda's rev happy S2000 may seem like opposites but really they have a lot in common. For example, the early Insight was assembled at the same Honda factory in Suzuka, Japan, where the Honda S2000 was assembled. Plus, both were purpose built to accomplish different but pretty specific goals. Calling the 2011 Honda CR-Z a sporty hybrid may seem like an oxymoron at first, but when you consider how much of the original Insight and the S2000 are actually infused into the CR-Z, the notion of a sporty, two-seat hybrid looks more like the next logical step in the evolution of the automobile.