Why the 2023 Acura Integra's Exhausts Are Shaped Like Curly Fries
If you were to find yourself beneath a new 2023 Acura Integra—or the mechanically related Honda Civic Si—we sure hope it's not because you were just run over. In that case, you might have more pressing things to worry about than the odd routing of the dual exhausts under the back bumper. But, hey, pretend you're on the ground, under an Acura or a Honda, wondering why there are pipes aft of the exhaust outlets shapes like curly fries. We were similarly curious (having put ourselves on the ground, under an Acura Integra, on purpose) and did some digging with Acura for answers.
What Does a Normal Exhaust Look Like?
Normally, exhaust piping follows relatively straightforward routes from the engine to wherever the gases are intended to exit—usually the car's rear end. This typically manifests as straight-as-possible piping leading from the headers, which collect gases from each of the engine's cylinders in individual pipes and merge them into one or two outlets that flow into a catalytic converter, to a series of resonators (for shaping or quieting the noise) and mufflers and, finally, the tailpipes.
There are a few bends here and there, mostly so the piping can clear things like the rear suspension, the fuel tank, or other obstacles, but conventional wisdom holds that they don't double back on themselves or otherwise make any unnecessary trips side-to-side.
How the Acura Integra's Exhaust Looks
The Integra's post-cat piping (aft of the catalytic converters) is a bit different. As we mentioned previously, this setup is nearly identical on the Honda Civic Si, which shares a platform, engine, transmission, and general layout with the new Integra. While the piping follows a relatively traditional central pathway rearward, toward the back of the Integra, via a small tunnel, upon reaching the rear axle area, it splits into a T-shape, with one pipe turning to the right and another to the left.
These two pipes bend slightly rearward and lead to small resonators, one per side, before taking a 120-ish-degree bend toward the vehicle centerline, followed by another (by which point the pipes are now flowing toward the front of the car), followed by another bend that points the piping back to the side of the car, and finally a gentler 60-ish-degree bend that spits the exhaust straight back, out from beneath the Integra's rear bumper. Why?
According to Honda, those squiggles in each exhaust outlet are, in fact, silencers. They serve essentially the same function as a muffler—Honda calls them "coiled-type silencers"—and their curious shape is highly intentional. While, like everything on a modern vehicle, their shape is somewhat influenced by the allowable space within the bumper and underbody area behind the rear axle, the specific pathway that piping takes plays a crucial role in the surprisingly guttural low-rpm sound the Integra and Civic Si make.
By snaking the exhaust piping into that circular route, Honda is lengthening the exhaust pathway, lowering the resonance frequency without using a traditional muffler . Honda engineers tell us that the design as first installed in the Si also emphasizes the 300Hz to 600Hz frequencies "to deliver a more aggressive sound." Skipping the muffler, Honda also was able to achieve that sound with a 27-percent increase in exhaust flow.
Good Vibes, Different Volumes
The old Honda Civic Si, you'll recall, featured a central-exit exhaust that spit gases from two tailpipes clustered at the center of the bumper. Compared to the new Si and its Integra sibling, it used two large mufflers in a somewhat unusual configuration: The same central post-cat piping flowed into a T-split, with each pipe flowing into the end of a transversely arranged muffler, one on each side of the car. Gases exited those mufflers about an inch from the inlets, reforming into a T before the piping exited the back of the car.
Doing some visual measurements—okay, by the seat of our pants here—the new, muffler-less exhaust setup has more piping. I.e., it's longer, mostly by replacing the old car's length of muffler with pipe, and then spinning that around into loops at each rear corner of the car. It's cool to see the progression of this concept by the engineers, as the new and old setups are clearly somewhat related, only the new version sounds much better, particularly at idle and lower engine speeds. And that's all things being equal, literally. The new and old Si, and by extension, the Integra, utilize the same turbocharged 1.5-liter I-4 engine, and the 11th-generation Civic's platform—again, shared with the Integra—is a modified version of the 10th-gen setup. We didn't note any untoward booming, either, despite the exhaust note being audible in both the Honda and Acura at highway speeds.
For higher-rpm duty, Honda and Acura lean on Active Sound Control—in essence, augmented engine noises and, in the Acura, some active sound cancellation via the audio speakers—to amplify good noises and tamp down on less desirable ones. The tuning of these setups are different in each car; the Honda notably amplifies the engine note, more so in its Sport drive mode. In the Acura, we're told that augmentation was turned way down, with the focus pivoted from outright sporty volume to shaping the noises already in play for a more refined effect.
Of course, the sounds made by the 2023 Integra or the Honda Civic Si are only small parts of both compact cars' appeal. The Si is clearly sportier than the Integra, with a firmer ride and louder augmented noises and no available automatic transmission (you'll get the best-shifting six-speed manual available this side of a Porsche and like it), while the Integra delivers most of the Si's athleticism with greater overall comfort, refinement, and richer features. Both are fun to drive, attractive small cars. And owners of either one can blow plenty of hot gas about how weird their exhausts are.
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ProsEngine apparently runs on TanneriteBalanced chassisStupid quick ConsToo many drive mode settings for someAWD adds some heftThat faceThere are two places where you'll probably never catch a glimpse of the new BMW M3's garish front end: from its driver's seat and, anyone sharing the road with one, from another car. Why? Because it'll take some fairly exotic machinery to keep up with, let alone pass, the BMW M3 Competition.Even when the M3 is coming at you, it'll streak by so fast, those big ol' vertical nostrils will seemingly blur into wider shapes that recall BMW's kidney grilles of yore. Whatever your thoughts about it, BMW did ensure the M3's sniffing schnoz shovels a ton of air into the engine bay, where its fierce 3.0-liter twin-turbo inline-six lies.BMW says the engine produces 503 hp and 479 lb-ft of torque. But man, it seems like there's no way this I-6 punches below 600 hp. Equipped with BMW's available xDrive all-wheel drive, the M3 Competition we tested shoots to 60 mph in 3 seconds flat. The quarter mile is dispatched in 11.1 seconds at 124.7 mph. That's Porsche and performance electric vehicle territory.The 630-hp Lamborghini Huracán STO bests it by just two tenths to 60 (2.8 seconds); the advantage of the 720-hp Mercedes-AMG GT Black Series is even slimmer—just 0.1 second. How can we reconcile that the M3, despite loading each of its horsepower with 7.8 pounds, somehow keeps up with those supercars, which carry 5.1-5.4 pounds per hp? We can't. BMW historically has underrated its beefier engines, but this is egregious.As features editor Christian Seabaugh summed things up, "It's just hilariously unhinged." There exists a drive mode where power is only sent to the rear axle, with predictable results. But you needn't activate the RWD setting for lurid oversteer. Forget chucking the M3 into a corner; you can just as easily induce drifts by pressing harder on the gas with the steering wheel turned. BMW's xDrive seamlessly sends so much engine torque to the rear wheels that you'd swear the car is rear drive.Speaking of, compared to the rear-drive M3 Comp he'd driven previously, senior features editor Jonny Lieberman bemoaned the heft, which he swore he could feel the M3's AWD gear added to the front axle. Indeed, some judges found it was often necessary to briefly lift off the gas or dab the brakes to get the M3's mass to transfer to the front for optimal turn-in, especially on the Streets of Willow Springs—a behavior Lieberman insisted was the result of the hundred or so extra pounds the AWD M3 Competition carries up front. But without a rear-drive M3 Comp on hand for comparison, most didn't find it disqualifying.More noticeable are the personality shifts from the previous M3 to this one. Gone is the sensation that the M3 tries to pummel the earth into submission with its overly firm suspension and heavy controls. In its place is a pleasant new delicacy to its dynamics. The suspension seems to have more travel and compliance, the body is allowed to roll and pitch slightly rather than remaining stiffly dead-level at all times, and even in the sportiest modes its steering is almost light.This smidge of movement lends the M3 a more natural feel, and you can easily detect where you are in its grip envelope by dint of the body lean. Our shoulders like the transition to the less weighty steering, which, along with the suspension's newly up-on-its-toes feel, gives the M3 Competition a furtiveness to its responses that's nearly Alfa Romeo-like.This harmonic lightness let several editors settle into a satisfying, fast-paced flow. On the Angeles Crest portion of our evaluation, where the M3 changed several judges' minds, Lieberman was able to keep pace with features editor Scott Evans driving the Mercedes-AMG GT Black Series. Of the two, only Evans could spot the M3's awful nose—in his mirrors—as it bore down on his 720-hp über-sled. Alexander Stoklosa 2022 BMW M3 Competition (xDrive) Specifications Base Price/As tested $77,895/$108,545 Power (SAE net) 503 hp @ 6,250 rpm Torque (SAE net) 479 lb-ft @ 2,750 rpm Accel, 0-60 mph 3.0 sec Quarter-mile 11.1 sec @ 124.7 mph Braking, 60-0 mph 105 ft Lateral Acceleration 1.03 g (avg) MT Figure Eight 23.3 sec @ 0.89 g (avg) EPA City/Hwy/Comb 16/22/18 mpg Vehicle Layout Front-engine, AWD, 5-pass, 4-door sedan Engine, Transmission 3.0L Turbo direct-injected DOHC 24-valve I-6, 8-speed automatic Curb Weight (F/R DIST) 3,899 lb (54/46%) Wheelbase 112.5 in Length x Width x Height 189.1 x 74.3 x 56.4 in On Sale Now Show All
With so many wings 'n things, the newest Porsche 911 GT3 RS looks like it could fly. Before you even think about this über-911-GT3 taking flight, let us assure you, all of those spats, spoilers, flaps, louvers, and so on are there precisely so that this sports car stays firmly planted on planet Earth. They have the added side effect of signaling to the world that you didn't settle—if that's the right word—for the already excellent 911 GT3, itself a track-ready missile that so impressed us we awarded it our 2022 Performance Vehicle of the Year award.Aero, DynamicsIn what could be the most Germanic understatement of the year, Porsche says "The purposeful look of the new 911 GT3 RS is characterized by the large number of functional aerodynamic elements." Yes, the "purposeful look" Porsche refers to is the eye-popping array of body add-ons that regular GT3s lack and the tallest rear wing ever fitted to a production Porsche vehicle. Like on the base GT3, the RS's rear wing is of the swan-neck variety, in which the supports stretch up and over the plane of the wing, mounting to the horizontal surface from above. Unlike the regular GT3, the RS's wing is taller than the roof, with a hydraulically adjustable upper section.That adjustable piece works in concert with a race-inspired drag reduction system (DRS), which at the press of a button moves the wings to a lower-drag position to achieve higher straight-line speeds. Conversely, under hard braking, the rear wing can flip up into an air brake position. Porsche has made the various splitters and canards on the nose similarly adjustable, a move made possible by sacrificing the front trunk entirely to a lay-down radiator. Air exits that radiator via a pair of huge holes in the hood, flows over the roof, and is directed to the sides so that the engine air intakes in the rear—remember, 911s are rear-engined!—ingest cooler air.Along with a larger rear diffuser, those meaty louvers atop each front fender (for evacuating wheel-well pressure), and reworked rear fenders for improved airflow, the 911 GT3 RS is altogether more focused than the already sharp GT3. Downforce in the RS is up big time as a result, three times more than what a "normal" GT3 produces at 124 mph (for a total of over 900 lbs). At 177 mph, the GT3 RS generates 1,895 lbs of downforce.The Mechanical StuffPorsche takes so seriously the GT3 RS's aerodynamics, that it didn't stop at adding those wings all over the body. Its engineers turned their attention to the RS's mechanicals, too, reshaping the suspension links with airfoil-shaped profiles, a move that is said to contribute 88 lbs of downforce at "top track speed" at the front axle alone. According to Porsche, these new links increase the GT3's track width by a mighty 1.14 inches in front.To help overcome some of that extra aero, the 4.0-liter flat-six engine retains the same one-throttle-body-per-cylinder layout as the non-RS GT3 but receives new camshafts and sees peak horsepower rise from 502 hp to 518. It comes mated to a seven-speed dual-clutch automatic transmission with a shorter final-drive ratio than the non-RS GT3 and little air intakes under the body that help cool it. Porsche, always conservative, estimates the GT3 RS is 0.2 second quicker to 60 mph than a 911 GT3; given how we recorded a 2.7-second rip in dual-clutch 911 GT3 last year, figure on the RS being mind-bending. Top speed is said to be 184 mph.Huge brakes help slow things down, with the front caliper pistons growing a few mm larger in diameter than those on the GT3. The front rotors thicken by 2 mm to 36 mm; step up to the carbon-ceramic brakes, and the rotors grow by 2 mm in diameter up front (410 mm) and 10 mm in back (390 mm). Also, as on the GT3, the RS gets a rear-wheel-steering system, albeit tuned along with the rest of the suspension for sharper response, and drivers can independently adjust the compression and rebound settings for the front and rear via buttons on the dashboard. There also is a rotary drive mode dial for selecting Normal, Sport, and Track modes (with the DRS button in the middle) on the steering wheel.What a Lightweight!Porsche says the GT3 RS weighs just 3,268 pounds, thanks mostly to the carbon-fiber door skins, front fenders, roof, hood, and seat shells. Want some of that carbon fiber on fuller display? The available Weissach performance package leaves the carbon naked on the roof, hood, rear wing, and door mirrors; the kit also includes forged magnesium wheels that shave 17.6 pounds of unsprung weight from the car.Also lightweight? Your wallet, after you buy a 2023 Porsche 911 GT3 RS. The car starts at $225,250 (about $60,000 more than a normal GT3) and goes on sale early in 2023. Deliveries begin in the spring, and those with reservations can also choose to pay even more and get a Porsche Design Chronograph watch that incorporates titanium and various nods to the RS's styling.
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There's nothing like shifting your own gears in a sports car like the 2022 Toyota GR86. With EVs taking over the market, the manual transmission is once again at risk of peril. Fortunately, a patent filed by Toyota with the US Patent Office was immediately spotted by the forums describing a complex new system to simulate the experience of driving a manual transmission, now without any of the thrilling danger of stalling.What Is It?When it comes to an EV like the upcoming Toyota "Sports EV," there is no gas engine that can stall out. That used to be the whole reason you need the clutch and a gearbox—to keep the engine from stalling, and to transition between gears, obviously. Why would Toyota bother having something like this on a car with no gears and likely near-instant torque on command?The patent filed by the Japanese brand a few months ago, but published this week, describes a system that uses a fake clutch, fake shifter, a three mode selector, and programming at the controller to simulate the experience of driving a manual transmission, just without the stalling.Full Manual ModeSo how does the patent say it works? Essentially, when you shift the "transmission shifter," the prospective EV's motor controller will increase or decrease the voltage—and, thus, the magnetic field controlling the rotor in the motor—and this effect is meant to simulate the torque feeling of each gear. There are three modes described in the patent.Both "clutch" and "clutchless" modes, as we're calling them based on what we see in the patent documents, operate this way. Some EVs do use a clutch to decouple and idle a permanent-magnet motor when it's not needed. However, that is not what is being operated in this mode. A third, automatic mode, lets the driver ignore the clutch pedal and shifter altogether, and operates as a traditional EV.The patent's clutch mode includes the need to operate the clutch pedal—and yes, there would be a third pedal in this car, but again, there is no true clutch being operated here. The voltage is changed to act as if you're not generating enough torque to move the vehicle. The motor won't stall and require you to restart it, it just won't go very fast or just won't move, like tugging on a gear or starting on a hill in a traditional car.No Clutch, No ProblemWhen operating in the other, clutchless mode, it will act similar to a DCT equipped vehicle using a regular stick shifter. You select the gear with the shifter, the controller modifies the voltage to the motor for each gear, and you "shift" through the "gears" to get the torque you want.The driver doesn't have to do anything with the clutch pedal in this mode. It's basically like knocking a normal automatic car into the "S" mode, where you can toggle "+" and "-" to control the gears with no clutch pedal.What Transmission?The automatic mode (again, our description based on what we saw in the patents) will act as a normal, "transmission-less" EV. The Toyota patent details how each mode calculates the torque the motor sends to the wheels, the torque demanded by the driver in relation to the throttle pedal and gear selector, and the amount of torque demanded by the throttle pedal position.There is even talk on how to train each mode to fit a specific driver profile with this type of pseudo-manual. It's unclear if this system would be built on current Toyota EV architecture and powertrains, or require broader vehicle development to be adapted to future cars.Early EV Conversions Did Have TransmissionsWhile early EV enthusiasts did stick a real transmission into their conversion projects, they mostly did it to try and assist the lackluster power and capacity available from lead-acid and nickel-cadmium batteries of the time, along with rudimentary controls for the motor. Most projects didn't even use the clutch or torque converter, and instead the motor was attached directly to the input shaft of the transmission.Today, thanks to lithium battery technology and controllers that can withstand higher amperes—along with much better cooling technology—you can truly build a car with monster V-8-like torque with battery power. The transmission just isn't needed as the motor actually potentially spins faster than is usable, and a reduction box is usually attached to the motor before heading to the wheels on EVs already. Perhaps plans could have this new EV "manual" replace or assist the current energy-reduction principle.Will It Stick?As a performance driver, you really want to have full control of your vehicle, but it gets tricky to continue to satisfy drivers with the input of a computer and more advanced technology. Not only is it technically obsolete, but it's also that little bit slower to shift, and it does force drivers to take their hands off the wheel. It's why a majority of race cars today utilize paddles behind the steering wheel rather than a stick that you must move around in a gate or even sequentially—speed, and a little intended safety.But we're not all racing drivers, and we have grown to love the manual transmission for the control it hands the driver. Heel-toeing into a corner to get the RPMs right is sublime. Sometimes you get a better lap time, being able to throttle the right amount of power down as you accelerate out of the corner if you know what you're doing. Some worry over major automakers pivoting to electrified technologies that completely render their charming stick and pedal technically obsolete. They want that feeling of rowing your own gears and operating a clutch. There isn't anything saying Toyota will bring this out, but it's exciting to see the brand thinking for enthusiasts, and worrying about making sure the future is still fun.
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