2015 BMW M4 vs. 2015 Lexus RC F Comparison
With Nearly 900 HP Between Them, These Luxury Coupes Make Quick Use of Roads - and Tires
You may find yourself crossed up in a luxury car, steering turned opposite the direction of the road, the remnants of tires following behind. And there may be a moment when, between the giggles, you find it strange that this kind of car exists. How would you classify these two? They started as luxury coupes -- something once intended to be well-appointed and comfortable -- but now they have more power, stiffer suspensions, and locking differentials so you can powerslide.
And boy, can you powerslide. The makers of these two cars will tell you about lap lateral g's and suspension kinematics, but the ease with which you can destroy their rear tires in wild displays of immaturity says differently. Think of the untold millions invested to satisfy us kids; we've built rockets that go to space, but all we want to watch is the fire from the engines.
In this case, it's BMW and Lexus, and this is how we got here: The former decided at some point in the 1980s that it would be neat if its sedan were faster than Mercedes-Benz's sedan around a racetrack, and a legend was born. Flash-forward 30 years, and down the family tree falls the M4. It's grown substantially in size and weight, but it's never been faster or as capable.
Lexus is the relative newcomer, creating a performance division in 2006 with its own letter: F. It stands for Fuji Speedway, where Lexus performs vehicle development, and the shape of the badge supposedly comes from a turn or sequence of turns on the track. The car here wearing that badge is the RC coupe, and regardless of the official definition, after driving it you might think F means Fun.
Funky best describes its design. The outwardly aggressive, in-your-face RC F looks good from a distance; its proportions and bolder cues give an appearance of something between LFA and IS F. The closer you get, though, the less successful that blend becomes. Strange details poke out everywhere -- what's going on with the side skirts, those headlights, that grille? It's a different look, for better or worse, and at minimum you can appreciate that Lexus really went for it.
Inside, the theme is consistent, though not as off-putting. The quantity of details and quality of materials make the RC F a far more interesting car to sit in. The LFA-inspired shifting digital instrument cluster is just cool, and it makes neat changes when you switch between driving modes. Put the car in the most aggressive setting, for example, and the tach grows and centers itself in the instrument cluster. It also has some fun toys, like a g meter that draws your lateral and longitudinal peaks in a circle. It challenges you to make that circle bigger by pushing the car harder.
"The M4 is the fast car for people who want to blend in."
Subtlety reigns with the BMW. It, too, is nicely proportioned but remains so as you get closer. Its details are cleaner, and the car appears more refined—it doesn't bare its teeth at everything. Skip the attention-getting paint options (like the pictured Austin Yellow Metallic), and people might mistake it for a standard 4 Series. This is the fast car for people who want to blend in. Past the smattering of carbon fiber inside, the new seats offer good support, the steering wheel feels good, and we always welcome a head-up display, but the M4's interior feels remarkably plain after the RC F. We respect the simplicity, but there is an absence of occasion.
In a strange turn of events, it's the Japanese car with the big V-8 and the German one with the small-displacement turbo mill. And with this comes a functioning demonstration of the advantages turbochargers bring and the things they take away. BMW's twin-turbo 3.0-liter I-6 makes an unarguable point in terms of power delivery, offering its peak 406 lb-ft of torque seemingly the second you apply full throttle and pulling strongly to redline. It feels overpowered in the best way, as if its engine were one size over the needs of the chassis. But while the power itself is fun, the sound of applying it pales in comparison to the Lexus. At the right engine speed and throttle load, a flap in the RC F's engine bay exposes the cabin and exterior to a deep intake bellow that's topped at redline with a soft beep, telling you it's time to do it all again in the next gear. It doesn't sound pretty but is wonderfully aggressive. The M4's timbre sounds mechanical and grainy in contrast, lacking depth.
Neither of these two has a clutch pedal. While the M4 comes standard with a six-speed manual, ours had the optional seven-speed twin-clutch gearbox, and the Lexus' eight-speed is the only transmission available. Both work well enough to make you seriously debate the worth of a manual, offering responsive upshifts and well-controlled downshifts. In manual mode, the RC F's transmission locks up the torque converter from gears second and up. Standard RC Fs come with a Torsen differential, but ours employed a driver-controllable torque-vectoring differential that biases power through a pair of electric motors and planetary gearsets.
For as different as the two look and sound, both cars are similar in size, sharing dimensions within tenths of an inch. So it's surprising to learn that the Lexus weighs 441 pounds more than the BMW. Why? According to Jonny Lieberman, the F team aimed to increase the RC F's rigidity but had to keep costs down. The resulting chassis is part GS (front), last-gen IS convertible (middle), and current IS (rear). The byproduct is weight. Lexus combats this with 42 hp more than the BMW, which brings the weight-to-power of both cars within 0.2 lb/hp. Alas, the M4 remains the faster car in our tests. Its less-frustrating-than-before-but-still-more-complicated-than-it-should-be launch control and broader torque band help it pass the quarter mile 0.5 second and 5.6 mph faster than the Lexus. The same goes for braking and road holding. The BMW gets more power out of its Michelins and optional carbon-ceramic brakes, stopping 9 feet shorter from 60 mph. It also completes its figure-eight lap 0.7 second faster and generates 0.04g higher average lateral grip in the process.
While the test numbers give the M4 the edge, the real world proves more of a level playing field. If you forget the numbers, you'll have a great time in either car. How can you not? They are, after all, luxury hot rods with precise steering, sharp handling, and hugely enjoyable, 400-plus-horsepower powertrains.
What becomes apparent is that when pushed, the BMW drives like the Lexus looks, and vice versa. The M4 certainly feels faster—a product of its lower weight and meaty, torque-filled powerband—but the RC F remains no less satisfying. It's also easier to approach; you feel like you can reach its limits after two turns. It offers stability in surplus, dropping the challenge of high-speed corners but not the fun. Its torque deficit and weight surplus only become apparent in tight second-gear corners where you have to wait for the engine to get back up to speed. Drifts are available but don't come on unless provoked. When prodded, the RC F happily produces tire smoke.
The M4's higher performance threshold means it takes a bit longer to get comfortable with, but it offers more reward. The M4's electronically controlled differential and suspension setup offers the rear end as an additional handling tool, allowing the driver to change the car's attitude mid-corner. Roll into the throttle after the apex, and the M4 tightens its line. Perfecting use of this tool takes some practice, though, as the M4's torque delivery can transform those adjustments into slides of rapidly increasing lunacy. Go without supervision long enough and you'll mark every corner you drive through with long black lines.
"When pushed, the BMW drives the way the Lexus looks, and vice versa."
We drew quite a few new lines around our local Streets of Willow racetrack where resident hot shoe Randy Pobst set lap times and gave impressions. Those lap times? They fell within 0.3 second of each other with the M4 ahead, no surprise considering the advantage it held during our tests.
Per Pobst, it came down to the BMW's propensity to oversteer versus the Lexus' stability. The M4's tires "want to be hooked up; they don't want too much slip angle," Pobst said. "By the seat of my pants, it felt like I could go a lot faster by being very gentle with the throttle in the middle of the corner and not asking the tires to do too much accelerating when it was busy cornering." And the RC F? "It's a very stable car, with a little bit of understeer late in the entry and in the middle," he said. "It was an easier car to drive fast than the BMW because it had far less power oversteer. It converted its power into acceleration better than the BMW would."
While Pobst liked the RC F's ability to translate power on corner exits into acceleration, he preferred the M4's body control. "The BMW is much better damped than the Lexus," he said. "The RC F is too soft for track use, which is not a condemnation -- it's not a race car; it's a sporty street car. On the other hand, if you have suspension adjustment, come on! Let's go! The BMW's are not adjustable, and yet they are plenty capable, and I do not think the car is horribly stiff on the street." Both cars come with all manner of buttons and adjustments. In the Lexus, a dial selects one of four drive modes, from Eco to Sport Plus, adjusting shift logic, throttle response, and steering accordingly. A TVD button adjusts the response of the differential to street, slalom, and track settings. Amusingly, Lexus calls the stability control's sport setting Expert mode, displaying it as such on the dash.
"If you forget the test numbers, you’ll have a great time in either car."
BMW separates the drive mode control into different buttons, offering one of three options for shift quality, throttle sharpness, steering heft, and stability control. If our tester had optional adjustable shocks, there'd be another button, too. Yet playing with these buttons offers little benefit. The most aggressive throttle setting, for example, makes the throttle act like more of a button than a lever, which isn't ideal considering how quickly torque comes on. The same goes for the transmission. "I don't like the most aggressive setting because I think it actually unsettles the chassis on upshifts," Pobst said. "It hits with such a bang." While an overabundance of settings is a minor annoyance, we found both of these cars excellent at producing tire smoke and smiles. We preferred the Lexus around town, as it's a more interesting car to sit in thanks to its wealth of technical and visual details. The styling may be a large miss, but we admire the effort. And we were genuinely impressed with the ground the RC F made up on the racetrack. It offers performance similar to the M4's, but it feels friendlier.
Alas, we picked the M4 when it came down to the car we'd rather take home. Its engine lacks the Lexus' aural satisfaction, but its powerband over-delivers. Its suspension works excellently on a bumpy racetrack and isn't exceptionally rough on normal roads. Overall, it offers a higher performance envelope than the Lexus, and while it might take more time to get accustomed to, we found more engagement and satisfaction in the process. As driving enthusiasts, we simply enjoyed driving it more. Powerslides and all.
Bumper CarsBy Kim Reynolds
When the checkered-flag start-finish line disappears under the M4's front bumper after 1.55 miles of furious driving, the Lexus is 13 feet arrears the BMW's bumper -- a scant 0.3 percent of a lap behind. How did we get here? Let's rewind the tape to the beginning.
The two cars blur past the starting line with the M4 almost 4 mph faster, with the gap inching up to about 4.5 before Turn 1. By this point, the BMW has a 33-foot edge, a separation that will Slinky somewhat over the ensuing 84 seconds, but never disappear. To really understand what happened we have to rewind even further, to when they accelerate out of the last corner and approach that start-finish line. The final result is dictated by a simple drag race to the start that the BMW wins handily. Over the ensuing 14 corners, the Lexus sometimes gains with higher braking g's; the BMW offsets that with harder spurts of acceleration and higher speeds wherever the course challenges their stability. By the finish, the two are not quite being bumper cars, but are pretty close.
|2015 BMW M4||2015 Lexus RC F|
|DRIVETRAIN LAYOUT||Front-engine, RWD||Front-engine, RWD|
|ENGINE TYPE||Twin-turbo I-6, alum block/head||90-deg V-8, alum block/heads|
|VALVETRAIN||DOHC, 4 valves/cyl||DOHC, 4 valves/cyl|
|DISPLACEMENT||181.8 cu in/2,979 cc||303.2 cu in/4,969 cc|
|POWER (SAE NET)||425 hp @ 5,500 rpm||467 hp @ 7,100 rpm|
|TORQUE (SAE NET)||406 lb-ft @ 1,850 rpm||389 lb-ft @ 4,800 rpm|
|REDLINE||7,500 rpm||7,300 rpm|
|WEIGHT TO POWER||8.5 lb/hp||8.7 lb/hp|
|TRANSMISSION||7-speed twin-clutch auto.||8-speed automatic|
|SUSPENSION, FRONT; REAR||Control arms, coil springs, anti-roll bar; multi-link, coil springs, anti-roll bar||Control arms, coil springs, adj shocks, anti-roll bar; multi-link, coil springs, adj shocks, anti-roll bar|
|BRAKES, F;R||15.8-in vented, drilled, carbon-ceramic disc; 15.0-in vented, drilled, carbon-ceramic disc, ABS||15.0-in vented, slotted disc; 13.6-in vented, slotted disc, ABS|
|WHEELS, F;R||9.0 x 19-in; 10.0 x 19-in forged aluminum||9.0 x 19-in; 10.0 x 19-in forged aluminum|
|TIRES, F;R||255/35ZR19 92Y; 275/35ZR19 100Y Michelin Pilot Super Sport||255/35R19 93Y; 275/35R19 96Y Bridgestone Potenza|
|WHEELBASE||110.7 in||107.5 in|
|TRACK, F/R||62.2/63.1 in||61.2/61.4 in|
|LENGTH x WIDTH x HEIGHT||184.5 x 73.6 x 54.4 in||185.2 x 72.6 x 54.7 in|
|TURNING CIRCLE||40.0 ft||35.4 ft|
|CURB WEIGHT||3,604 lb||4,045 lb|
|WEIGHT DIST., F/R||52/48%||54/46%|
|HEADROOM, F/R||39.8/36.1 in||37.8/35.0 in|
|LEGROOM, F/R||42.2/33.7 in||45.4/27.3 in|
|SHOULDER ROOM, F/R||55.3/51.7 in||50.7/46.1 in|
|CARGO VOLUME||11.0 cu ft||10.1 cu ft|
|ACCELERATION TO MPH|
|0-30||1.7 sec||1.7 sec|
|PASSING, 45-65 MPH||1.7||2.0|
|QUARTER MILE||12.2 sec @ 117.8 mph||12.7 sec @ 112.2 mph|
|BRAKING, 60-0 MPH||98 ft||107 ft|
|LATERAL ACCELERATION||0.98 g (avg)||0.92 g (avg)|
|MT FIGURE EIGHT||24.2 sec @ 0.84 g (avg)||24.9 sec @ 0.80 g (avg)|
|1.6-MI ROAD COURSE LAP||83.73 sec||84.05 sec|
|TOP-GEAR REVS @ 60 MPH||1,750 rpm||1,550 rpm|
|PRICE AS TESTED||$85,225||$73,225|
|AIRBAGS||Dual front, front side, f/r curtain, front knee||Dual front, front side, f/r curtain, front knee|
|BASIC WARRANTY||4 yrs/50,000 miles||4 yrs/50,000 miles|
|POWERTRAIN WARRANTY||4 yrs/50,000 miles||6 yrs/70,000 miles|
|ROADSIDE ASSISTANCE||4 yrs/unlimited||4 yrs/unlimited|
|FUEL CAPACITY||15.8 gal||17.4 gal|
|EPA CITY/HWY/COMB.ECON||17/24/19 mpg||16/25/19 mpg|
|ENERGY CONS., CITY/HWY||198/140 kW-hrs/100 miles||211/135 kW-hrs/100 miles|
|CO2 EMISSIONS, CoMB.||0.99 lb/mile||1.02 lb/mile|
|RECOMMENDED FUEL||Unleaded premium||Unleaded premium|