Bodacious Curves

Here’s the thing,

Numbers rule the world, especially in the automotive world. You spend x number of minutes (or hours) in your car to get to a job to work x number of hours to bring home x number of dollars. Why? So that you can pay x number of dollars for your mortgage and support your wife (or husband) and x number of kids. Everything in our modern, data-driven lives is quantified, and our cars are no different.

Look at the Monroney Label, or window sticker, of any new car. Literally everything is quantified on that sticker. Pricing, power, emissions levels, and efficiency are all laid out in black and white for people to see. Grab a sales brochure and there’s even more. And while most vehicle purchases end up being an emotional decision, the short list that most consumers allow themselves to actually drive is compiled using the numbers on those stickers and in those brochures. There is one specifically that appears to baffle even the professionals though, power.

There’s an old saying: horsepower sells cars, but torque wins races. Think of your car as dinner out at a nice restaurant. Horsepower is your server. The restaurant hires people that look good, act pleasant, and function as the sole face of the restaurant. Torque is the set of chefs in the kitchen making your meal, sweating it out, getting the meal made. While the server, horsepower, is responsible for making sure you have a good experience with the restaurant, the chef, torque, is the one responsible for making sure your meal gets made and that it’s delicious. But here’s the thing: both work hand in hand to make sure that your evening goes off without a hitch and that you’re as satisfied as possible. That’s because they’re actually two parts to the same force.

Without getting too technical, horsepower is a calculated number using the amount of torque the engine is putting out at a specific engine speed. This means you’ve got two ways to make power: generate torque, or rev the engine high enough to amplify it into more horsepower. The ideal engine does both, generate high levels of torque and sustain it into higher revs where horsepower can keep it going. When you only have one or the other, performance suffers. That’s why two different engines, both putting out identical or near identical power levels can have vastly different performance figures.

A tale of two Bimmers: The E9X M3 is still a fan favorite. With a rip-snorting V8 that revs to over 8000rpms, it was the friend that you made sure to bring to every party, just to watch the antics he’d get into once he’d had a few. The F-Series M3 is a bit more refined, and makes it hard to believe that the respectable banker in the suit and tie used to be that same party-hound, although he still out-drinks everyone at the bar. Going between these generations, the car only gained 11 horsepower, but is able to achieve almost a half-second faster 0-60 time, with 2 fewer cylinders! That’s because replacing those two cylinders is two turbochargers, which help to cut the number of revs needed to achieve peak torque in half. What that means is that the car is generating more area “under the curve” through pretty much the entire rev band, particularly in the first half of the rev-range. For the 3 of you still with me out there, thanks for following along.

Sorry for getting out into the weeds on that one, but let’s think about it this way. In geometry, we learned how to plot functions. And after we learned to draw the lines, we learned the means to count the little boxes under the line. The faster you can make power, the greater your number of little boxes. And in this case, boxes are power, and power is speed.

Look, I’m not an engineer, I just play one on the internet. However, I am a car guy. And I have a challenge for other enthusiasts out there: take an interest in what the objects of your passion do. Learn the way they run and what every tick on the tach means for the car. Hopefully for the uninformed, this article has piqued something in your mind to reach for a better understanding of how your car does what it does. Otherwise they’re just boxes. And numbers on a sticker in the window.

And that, that’s the thing.

-Shawn

 

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