And loud is good.
Where do you measure the sound of a car to figure out which is the loudest? From the inside, where the driver hears it? At idle? Do you try and use a decibel monitor as the car goes by at full speed? Well, inside the car depends a lot on sound insulation, an exhaust at idle is no indication of what it will rise to when driven, and we don't have the budget to hire a track to test every car we drive. So, we've taken a completely unscientific approach for this list and based it mainly on our perceived experience with the cars and colleagues through the automotive industry.
A quick note on the decibel scale as we will mention some measurements: The decibel scale measures sound pressure level on a logarithmic scale based on the power of ten. That means that as the scale goes up, smaller changes in reading show a more drastic level of sound intensity. For example, 80 dB is twice as loud as 70 dB, and 90 dB is ten times louder than 80 dB.
If you want a loud sedan, you can always rely on AMG to deliver. We loved the sheer hooliganism of the AMG E63's 4.0-liter twin-turbo V8 and the noise it left in its wake. At idle, it weighs in with a 45-dB rumble, which according to experts, is the "lowest limit of urban ambient sound." At full throttle, it measures 81 dB from outside. Inside, it is a little muted as it's a luxury sedan, but we just rolled the windows down.
In 2019, the Jaguar F-Type in supercharged V6 form was recalled in Australia because it was too loud, measuring over 74 decibels when subjected to a drive-by test. The F-Type R is even louder, with a roaring, spitting, and popping supercharged V8 under the hood. It's loud enough that Jaguar has given it a quiet start-up mode and that this writer got yelled up by a cop when he forgot to take it out of Sport mode coming into the city. We're assured that, at full throttle, the F-Type R cracks 84 decibels. Sounds above 85 decibels are considered harmful for prolonged periods, and 84 decibels is what you'll hear being 100 feet away from a diesel train doing 45 mph.
Everything about the Lexus LC is a statement, from its looks to its sound, and we'll admit that we left it idling during our last test drive just to have a cup of coffee and listen to it burble. It is one of the most sonorous V8 engines around, but it's also good and loud when you drive it hard. It peaks at 88 dB with the throttle mashed and the rev counter rising, comparable to a propeller plane flying over your head at 1,000 feet. The coupe is prettier, but there's a genuine argument for getting the convertible to get even more of the LC's song into your ears.
Lotus's Evora GT is a visceral car, and not for those that like creature comforts like a cupholder that requires a double-jointed elbow or anything but the bare minimum of sound deadening for the cockpit. The supercharged V6, built by Toyota then turned into an animal by Lotus, positively shrieks at high rpm, and there's just a piece of glass between the engine and the driver's head. Out of sheer curiosity, we measured the Evora GT with an iPhone app at around fifty feet away and got a reading of 91 dB. We wouldn't walk into a courtroom with that number and defend it, but it's loud, raucous, and sounds fantastic.
A flat plane crank engine delivers a very special howl, and the Shelby GT350's 5.3-liter V8 can be heard from a long way off, even when it's not in Track mode. You may wonder why the GT500 doesn't make this list, and the answer is simple - they're both brutally loud, but the GT350 doesn't have a quiet mode. The GT350R redlines at 8,250 rpm and wails at 92 decibels with the throttle wide open. That's louder than standing next to an arc welder without hearing protection.
At the time of writing, the current generation Corvette doesn't have a ZR1 model available. We'll have to see if it's louder than the C7, which set one hell of a benchmark. The supercharged 6.2-liter LT5 is a monster and doesn't reach its 755 hp peak until 6,400 rpm and using 101-octane race fuel. It doesn't matter how you judge its sound. The Corvette ZR1 is loud at idle, loud as it accelerates, loud at full chat, loud from inside, and loud from outside. At wide-open throttle from outside, it's been measured at 99 dB. That's just a little quieter than a jet airplane heard from 305 meters away.
The 2019 Porsche 911 GT3 RS topped out at 9,000 rpm and at 102 dB. The 2022 911 GT3 RS... we haven't driven or got a measurement for. However, we suspect the 2016 GT3 RS will remain king of the loud Porsches from a real-world reading from Car and Driver that moved the needle to an ear-splitting 108 decibels. No matter what angle you listen to the madness that is the 2016 Porsche 911 GT3 RS, the cacophony of its race-tuned 4.0-liter flat-six can be heard. At 8,900 rpm it reaches its peak, and is the realm of being in the audience of a rock concert or within spitting distance of a jackhammer.
There's not much better in terms of sound than a naturally aspirated V10 at wide-open throttle, and Lamborghini's Huracán Performante brings the noise on the way up and down the rev range. We knew it was loud, but a couple of British journalists at Auto Express measured both the coupe and Spyder in second gear and revving out and came up with 109 dB for the coupe, a little louder than the Spyder model. We doubt that putting both the Huracán Performante and the 911 GT3 RS together in exactly the same conditions and measuring, in the same manner, would see the Huracán come out louder, and this isn't a purely science based list so...
It depends who you talk to about the 720S Spider. We see 99 dB most often given for its fire-breathing 4.0-liter twin-turbo V8 but, in an independent test, we've seen it called at 109 dB. However, it doesn't matter because, with the top down, the sheer level of noise only adds to the terror of laying 710 horsepower down through the rear tires of a 3,000-pound car. If you ever get the chance to drive or ride in one, take our advice and grab the opportunity with both hands.