If you were to chart new-car horsepower over the past ten years, the graph would look like the one for Lindsay Lohan arrests: flat, flat, climbing a bit, and then suddenly skyrocketing toward vertical. It was a little more than ten years ago that I first drove a car with more than 400 hp, the 2002 Chevrolet Corvette Z06. That level of output was such a big deal that the car had a badge on the side that read “405 HP.” Now my hedge trimmer has 400 hp, my lawn mower has 500, and the Corvette ZR1 has 638. For the next ZR1, bidding will start at 800 hp or I’m not even interested.
We’ve become so jaded so quickly that 500 hp isn’t even a big deal anymore. I mean, sure, it’s nice to have 500 hp. But you can get that in Land Rovers, Nissans, BMWs, Benzes, Jags, Cadillacs, Chevys, Porsches, Fords, and Audis. Ten years ago, a Lamborghini Gallardo or a Porsche 911 GT2 didn’t even have 500 hp. Today you can order a TRD-prepped Toyota Sequoia with 504 hp. If I had one of those, the answer to “Are we there yet?” would always be met with 504 horsepower’s worth of shut-your-yapper.
Now, an obvious question regarding this underhood arms race might be: Why? If we were all so happy when the E39-edition BMW M5 had barely 400 ponies, is it necessarily a better world when that number seems rustic? I’ve given this a lot of thought. And the answer is: of course.
There’s a wonderful democratization to the idea that today’s M5-level horsepower is tomorrow’s Ram Tradesman, or that my next-door neighbor can slap a supercharger and drag radials on his C6 Corvette and immediately begin knocking out Bugatti-like quarter-mile times. Sure, he may have maimed his transmission on one of those ten-second runs, but I’ll bet it was worth it.
Plus, bragging rights aside, Einstein’s theory of relativity says that the faster you go, the slower time unfolds for you. And nobody has enough time. So every moment I spend doing 150 mph on the autobahn, I’m aging a little bit less than the rubes in the slow lane. It’s just science.
But all horsepower is not created equal. Although inflated horsepower numbers are invariably sad and pathetic (remember when the mighty Mustang 5.0 was re-rated from 225 hp down to 205?), there’s nothing cooler than a sandbagged horsepower number. And right now, nobody understates horsepower like BMW.
A few months ago, I visited BMW’s Spartanburg, South Carolina, test track armed with a 321-hp Cadillac ATS 3.6. We set up an informal drag race against a 328i, and the claimed 240-hp BMW held nearly dead even with the V-6 Caddy. I know the BMW has two extra gears, but still: similar curb weights and an 81-hp advantage should’ve manifested itself as an easy win. When I commented to a BMW bystander about the 328i’s evidently magical 240 horses, he muttered, “Or 270 . . .” Which, if true, confirms the finely calibrated backside of our own Joe Lorio — during last year’s Automobile of the Year testing, Lorio returned from a drive in the 328i and declared, “That feels more like 270 horsepower.”
If the little 2.0-liter four-cylinder is overachieving by about 13 percent, then what kind of real-world power can we expect out of the mighty S63Tu, otherwise known as the M5 engine? The one time I tried to launch a new M5 with a heavy foot and no traction control, it laid dark strips of rubber until about 60 mph, when it started to crab sideways and I chickened out. So, 560 hp, huh? We can talk about gearing and torque curves and rubber compounds, but generally speaking, 560 hp shouldn’t enable a two-ton-plus sedan to roast its tires up to highway speeds. I smell a three-digit number that begins with a six. To test that hunch, I bring an S63Tu-equipped M6 to the dyno shop.
If you’ve never heard the M6’s twin-turbo V-8, the exhaust note sounds like a Hemi Dodge Challenger arguing with a flat-plane Ferrari 458 Italia. The secret is the patented exhaust manifold — the most expensive part on the car — which rearranges the exhaust pulses to hit the turbos with steady beats of turbine-spinnin’ gases. The result, besides that crazy exhaust note, is basically zero turbo lag along with great gobs of power. How great?
Well, when I ask BMW about the general widespread fibbing on the horsepower front, the explanation is twofold: one, horsepower is rated when engines are new, and once they break in they tend to make more power. Two, BMW horsepower is rated according to a kind of worst-case scenario — if BMW tells you that an M6 has 560 hp, then it has
560 hp fresh out of the showroom on a muggy 90-degree day with a potato in the exhaust pipe. (Dang you prankin’ kids!) On a cool 45-degree morning like this, with a broken-in car and 93-octane gas, it has more. A lot more.
Seven years ago, I wrote about the 2006 M5’s then-incredible 500 hp, speculating that “a team of mad German scientists probably right now are sketching out a 600-hp freak of a sedan.” Well, you can call me Dynostradamus, because the S63Tü put down 577 hp. At the wheels. Apply the standard (and overgeneralized) fifteen-percent assumption for driveline losses, and you get about 660 hp. Robert Tighe, owner of the dyno, glances at the numbers up on the computer monitor and declares, “If you see a BMW on the street . . . don’t mess with it.” Sage advice.
My toddler son has a Lightning McQueen Power Wheels car, and under the hood the dummy plastic V-8 wears a sticker reading “900 horsepower.” That’s silly, right?
Ask me in another seven years.