How much horsepower is enough?

Dear Car Talk

Dear Car Talk | Jul 01, 2008

Dear Tom and Ray:

I need some straightforward and honest guidance on how important torque and horsepower are for a small car. My husband recently passed away, and now I must downsize my F-150. I have done research during the past few weeks, looking for the best four-cylinder/automatic that would meet my needs. I am down to the Ford Focus and Nissan Versa. My question: The Focus has a slight edge in torque at 136 (at) 4250 rpm and horsepower at 140 (at) 6000 rpm, while the Versa has a torque listed at 127 (at) 4800 rpm and horsepower of 122 (at) 5200 rpm. Both have comparable size, curb weight, quality and warranty. I am just not sure if the difference is worth the slightly higher cost of the Focus. Can you tell me if it would make a positive difference in power and pickup during highway miles?

P.S.: Just a word about our family: My 11-year-old grandson recognized your voices when we went to the theater to see "Cars." He has heard NPR in his grandma's truck often during the past few years! --


RAY: First of all, we're awfully sorry to hear about your husband, Kathleen, but we're glad you're continuing to corrupt your young grandson in his absence.

TOM: When looking at power numbers (horsepower is the overall power of the engine, and torque is the amount of twisting power the engine can generate), it's not enough to take the numbers by themselves. You also need to consider the vehicle's weight.

RAY: Right. If you were asked to choose between two potential suitors, both of whom were 5 feet 9 inches tall, wouldn't you want to know that one of them weighed 375 pounds?

TOM: When we divide horsepower by the weight, we get a horsepower-to-weight ratio. That tells us that the Focus (.051 horsepower per pound) is, indeed, more powerful than the Versa (.045). But the question is, do you need that extra power? Because, when it comes to power, the gold standard that you're shooting for is "adequate."

RAY: My brother's been shooting for "adequate" for years, and has yet to even come close. But he's right about engine power. If you don't have enough, you can a be a menace on the roads, or put yourself in danger by being in the way of faster-moving vehicles. But if you have too much, you'll be paying for that extra power in wasted fuel every time you run the engine.

TOM: So, how do you decide what's adequate? Well, the best way is to drive the car. I suspect you're going to find both of these cars to be perfectly adequate, especially around town.

RAY: But don't limit your test-drive to around town. Try getting on a highway. In some parts of the country, where traffic is heavy, you really have to get up to speed quickly on a highway entrance ramp to avoid having an F-150, for instance, making intimate cooing noises near your rear bumper. So, try that and make sure you feel secure doing it.

TOM: Another factor is how many passengers you carry. Do you usually drive alone? Or do you take your grandson's basketball team out for milkshakes after the game? A heavier load calls for more power as well. So, if you often carry passengers, invite a few along for the test-drive, and try the highway test again. If your heart is in your throat as you try to stay ahead of that semi that's coming up on you in the right lane, that'll be a signal that you need a little more oomph.

RAY: But if you're like most people, and usually drive alone or with one other passenger, and death-defying highway stunts aren't a regular part of your routine, almost any four-cylinder car will provide adequate power.

TOM: So, drive them both again and see which one you like better. I don't think the amount of horsepower or torque should be the determining factor in this particular decision, Kathleen. And in either case, enjoy your new car.

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