John's Blog

Why peak horsepower doesn't matter...

My gearhead friends are certainly already foaming at the mouth thanks to the title, but the truth is, it doesn't. If you're gonna take your car out for track days at the Glen or Limerock, then yeah, it matters. Likewise, if you have some machismo driven need to stomp the kid next to your in a stop light shootout, then yeah, it matters. But for the average driver under normal conditions, it doesn't.

Consider the following:


Although engine B has greater peak HP, unless you wind it out like a riced out Civic, you're never gonna get to that extra power. Instead, the increased power band from 1500 to 4k rpm makes engine A far more drivable under normal conditions.

Now consider the torque curves for the same engines.


And that is why Americans like big block V8s. Not because of the power, but because of the plentiful low end torque. But, like Mhz, marketers hve convinced us that horsepower is all that matters; nevermind the gearing, torque curve or power to weight ratio.

Curious thing is, a small displacement turbodiesel will give you globs of torque at the low end, resulting in a car that is very drivable for the stated HP. After driving my car, Doyle couldn't believe it only had 90hp. It certainly doesn't accelerate like his 1.8T powered A4, but whne you consider I get 47 mpg, compared to ~30 for the A4 or my sister's Wolfsburg Jetta, it's a trade off worth considering.

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