Put your foot into the throttle of the 2018 Audi RS 5, and there is a great, glorious engine racket that represents the full measure of the 2.9-liter biturbo's 444 hp and 443 lb-ft. If you quickly glance down at the tachometer nestled amid Audi's renowned Virtual Cockpit, you'll see green-yellow-red cues alight as you approach redline. But with all 21.5 psi of boost urging you forward, you better get your eyes up, partner, because the horizon ain't that far away.

See all 275 photos

So who would buy an RS 5 coupe? Say you love the idea of a throaty Camaro ZL1, but your station in life might draw Charlie Brown squiggly-frowns and squinty foreheads from your hedge fund peers. Travel 4,300 miles east to Ingolstadt, and you have your solution, starting at $70,875.

In a previous review, Angus MacKenzie referred to the RS 5's engine note as "grainy." I'd call it "gargly." Either way, it's not exactly smooth. Nor is it meant to be. And although it will never replicate the full-throated, hide-your-children roar of the Camaro, the RS 5 has sufficient clout, grit, and muscle behind it. It ain't wimpy, either. Sixty mph arrives in a claimed 3.7 seconds—and Audi says its testing methods are conservative.

Sharp, precise upshifts through the eight-speed automatic transmission elicit a sharp bark from the exhaust, prompting the joker in me to mutter, "Gesundheit!" However, let off the throttle and coast a bit, and there is a touch of annoying drone from the muffler.

See all 275 photos

A word about "Auto" driving mode: That's really all you need, even if you are partaking in serious driving. The ECU and Quattro all-wheel-drive system understand what you are doing and respond appropriately. If you think you need the added gravitas of Dynamic setting—say if you are driving at eight-tenths or above—you'll be clocking 90 on a sweeping mountain road. The cops will hear you coming thanks to the throaty exhaust, and your velocity will confirm their aural suspicions. For those wanting to test the legs of rural law enforcement and the sturdiness of their jails, the RS 5's top speed is 155 mph, or 174 when equipped with optional 15.7-inch ceramic front disc brakes.

Around town, Comfort mode is preferable. You can throw it into Dynamic mode for quicker shifting if needed in the cut-and-thrust of rush hour. But Dynamic mode's associated grunts and growls are unnecessary unless you want everyone to think that Audi RS 5 drivers have replaced BMW M3 drivers as the arrogant asshats of the road.

Even in Comfort mode, there is a fair amount of dynamic vertical chop from sharp road undulations. Perhaps it was the 20-inch wheels of all our test vehicles; you can try the 19s if you think it will make a difference. With the 20s, check your spine and kidneys at the driver's door. And make sure your passenger has a strong bladder. Similarly, steering tip-in feel is crisp and precise, but midcorner adjustments feel a bit twitchy. Of course, this is an RS 5, not some wimpy S5. Graduating to the "R" requires a commitment, including sitting 7mm lower than its sibling.

See all 275 photos

Now, say you are at a track day and you need some specific settings to match the layout of the circuit. Getting technical, Individual mode allows the driver to adjust the Quattro rear differential, transmission shift points, throttle response, steering response, and settings for dynamic ride control with adjustable dampers. Did we mention the RS 5 has a self-locking center diff with active torque distribution to both axles? If you notice it kick in, you're a bigger stud than I am.

What does all this performance mean at the pump? Audi claims an 18/26/21 mpg rating per EPA measurements. But the RS 5's svelte looks mean it has to shoehorn in a 15.3-gallon fuel tank, meaning more frequent fuelings.

Although folks are buying the RS 5 for its performance credentials, it's nice to know Audi kept the inside refined. The panoramic Virtual Cockpit remains intact. Apple CarPlay and Android Auto hook right up, standard.

See all 275 photos

See all 275 photos

One pet peeve, however: The navigation map provides your next-step instructions from the bottom of the screen upward. Question: Who reads a book from the bottom up? I am sure an Audi engineer has a brilliant reason why they contradicted the entire literate world with this user interface, but I'll never believe it.

Among the slew of de rigueur standard safety systems is a pedestrian and vehicle collision warning and braking initiation system that works from 6 mph up to 52 mph. The standard park assist has front and rear cameras with excellent definition, though not as crisp and accurate as those in our BMW 530i long-term tester.

As for chatting with your companion (and there likely will be just one, as the back seat is really for 2+2 purposes), a fair bit of sound deadening was removed from the standard A5. A ton of road roar comes into the cabin on anything but velvet-smooth asphalt. But what do you want? You paid the extra dosh to get the "R" in front of S5. This is a purebred sports coupe but with more than a hint of nasty.

See all 275 photos