Automotive manufacturers are seeding the clouds of a worldwide performance downpour. Who's got the highest horsepower? Which one handles best? What's the quickest lap at the infamous Nuerburgring? Who wins?
We all do.
This seemingly limitless convergence of high-performance hardware continues to blanket our highways and whet our appetites. Not limited to passenger cars, high-output sport/utilities occupy one arm of this tempestuous storm.
The four PUVs (performance utility vehicles) you see here are the latest, most track-ready sport/utilities we've ever driven. It wasn't long ago that exceptional sport sedans would boast about the performance numbers any one of these grocery-getters makes. Yet, with this hyper performance, we're happy to report that every one of these 315-plus-horsepower, two-ton-plus models meets or exceeds California Low Emissions Vehicle status. Like low-fat chocolate cake, you can have your fun and feel good about your indulgence.
In many ways, these sporty extroverted SUVs are designed and built for the American buyer. Sure, they're sold in other markets, but not in the numbers the high-output versions are here. Six-cylinder or even diesel models can be found overseas. Americans have an insatiable appetite for V-8 performance and sport/utilities, so why not combine the two?
Our mission for this comparison was to put the claims of our guests to the test. This isn't a beauty contest nor a tally of nifty electronic features. This is a flat-out performance test. Each player attempts to maintain or further the reputation of its maker while claiming superiority among its peers.
While these makers' marketing departments wish to avoid the term sport/utility, we call 'em like we see 'em. In our eyes, a tall wagon-shaped package featuring an all-wheel-drive chassis with second-row (and third-row in one case) seats that fold flat is a sport/utility. BMW would prefer that we call the X5 a "sport activity," while Cadillac would like to see "performance utility" attached to the SRX. Meanwhile, Infiniti describes the FX45 as a "bionic cheetah" or "premium crossover" vehicle. Only Porsche is content with its Cayenne nomenclature, saying it "brings exceptional dynamic capabilities to the sport/utility category." We'll see.
One sunny day, we put each vehicle through our usual battery of five track tests (acceleration, braking, slalom, skidpad, and figure-eight). We also wanted to combine all these behaviors in a separate lapping session at a racetrack, using the Streets course at Willow Springs International Raceway. Then it rained on our parade. What seemed like bad luck at first became an even better demonstration of how well all four put their engines, brakes, suspensions, tires, and AWD systems to use on a wet surface. The differences in philosophy and hardware jumped out at us as plainly as the badges on our test subjects.
Fourth Place: BMW X5 4.4i
BMW launched the X5 in the U.S. in model-year 2000. The mission of the vehicle was to offer the hallmark BMW driving experience in a sport/utility silhouette. What we found from the very first test was that it hit the bull's-eye. Yes, it drove as a BMW should, but it also offered the high seating position, load flexibility, and off-pavement abilities of an SUV--the best of both worlds. Since then, the X5 has been offered in six-cylinder and high-output 4.6is variations. No M-spec model has yet been produced. This year, the 340-horsepower X5 4.6is has been withheld, with a more powerful 4.8is looming on the horizon.
Instead, BMW has reinvigorated the 4.4i with several new features: a 4.4-liter, 315-horsepower V-8 engine, a six-speed automatic transmission, a more flexible AWD system, and new sheetmetal from the windshield forward with new exterior lighting front and rear. What was once a perfectly handsome X5 looks and sounds even better in 2004. The new engine offers the flexibility of infinitely variable intake- and exhaust-valve timing as well as a fully variable intake manifold. In concert with the six-speed, the result is a throatier presence and an amazing improvement in fuel economy from 14-city/18-highway mpg to 16/22, or the best in this test.
The X5 4.4i we tested for this comparison was fractionally slower to 60 than the X5s we've tested in the past--perhaps due to the new six-cog gearing or the 100 pounds of new weight versus previous X5s--with a 6.9-second sprint. On the flip side, it tied a higher-output 4.6is in the quarter mile (14.9 seconds at 94.5 mph), showing that horsepower does indeed rule the dragstrip. Still, in this crowd, it managed to effectively tie the 340-horse Porsche Cayenne S step for step, both having to move about 15.5 pounds of vehicle per horsepower.
Once considered in the neighborhood of sport sedans, a 61.7-mph slalom run was good enough for only third place in this crowd. In typical BMW fashion, the X5 remained poised and confident, giving up grip when thrown too hard at a cone. Its quick steering and communicative chassis gave the BMW high marks for ease in the slalom, and it felt better than the numbers suggest.
The X5 earned another third place for its brakes with stops from 100 and 60 mph taking 336 and 119 feet respectively. As with the handling tests, the feel of the X5 was better than the numbers it produced--no front-wheel stand, no swerving, and no surprises here. On our figure-eight test, which combines bursts of acceleration, braking, and cornering, the X5 once again edged ahead of the Cadillac by just 0.65 second and 0.01g on its best lap.
Fourth Place: BMW X5 4.4i cont...
At the wet racetrack, we thought the X5 finally would leap out ahead of the much larger SRX, which had been nipping at its heels on every other test. The X5 made the circuit a second quicker than the SRX at 1:13. We found the X5 produced terminal understeer even under full throttle in a high-speed sweeping turn, where two of the others' AWD systems seemed to overcome this tendency.
BMW's new xDrive AWD system is a departure from last year's, which used a planetary center differential to permanently apportion front/rear torque at 38/62 percent.
Just for the record, we made laps in all four with their stability systems activated (and busy) to make sure we weren't unfairly disabling a system that might produce better lap times. It turned out all four made their quicker laps with the systems shut off.
The new multidisc-clutch transfer case continually interprets a multitude of dynamic data to vary the amount of power being routed to front or rear axles. In normal driving, the system operates on a 40-front/60-rear split, but it can make an even 50/50 or lopsided 0/100 front/rear split under certain circumstances. Unfortunately, one of the circumstances where the front wheels were effectively undriven was severe understeer as described above. This means that, even under full throttle in a fast corner, only the rear wheels were getting power, producing a bigger push. The solution was to gradually lift out of the gas until the front wheels bit and obeyed the steering input.
Certainly, the X5 is a beauty inside and out, and we can appreciate its flawless build, communicative driving dynamics, and strict adherence to BMW values. However, the X5 just can't run with this capable pack at the track.
Third Place: Cadillac SRX V8 AWD
Imagine our surprise when the Cadillac SRX rocketed to the quickest acceleration runs of the whole group. So out of the ordinary was a 6.4-second sprint to 60 mph, that we dove into our records to discover that it beat our previous SRX V-8 AWD 0-to-60 test by 0.7 second; by 100 mph, it was 2.5 seconds ahead of the preproduction SRX we had for our 2004 Sport/Utility of the Year competition. Hot rod? Maybe, but this one was a runner, for sure. In terms of dimension, the SRX is the longest and tallest vehicle in the test, which made the feat even more incongruous.
Driving this SRX to first place on the dragstrip was the new-gen Northstar V-8 producing 320 horsepower. As with all the V-8s in this test, it features all-aluminum construction, dual-overhead camshafts, and infinitely variable timing on intake and exhaust valves. Despite its large appearance, the SRX had a horsepower-to-weight advantage over everything but the Infiniti FX45 (about 13.8 pounds-per-horsepower versus 13.7). With its five-speed automatic, the SRX clicked off upshifts just shy of its 6700-rpm redline every time.
What makes the SRX so comfy and roomy inside (it's the only one here with a third-row seating option) also makes it unhappy in the handling tests. A long 116.4-inch wheelbase and ultralight steering made it feel like a battleship among destroyers. We managed to outpace the preproduction SRX in the slalom by a sizeable margin, yet this one still fell to the back of this pack in the slalom.
On the other hand, the amazing magnetic-fluid shock absorbers were so quick and seamless in their ability to smooth out rough public roads and tidy up aggressive driving at the track that we could scarcely tell they were there at all. These shocks don't require any servos operating valves within them. Rather, the fluid changes viscosity based on the presence or absence of an electric charge. Like flipping a light switch, the shocks change damping rates nearly instantaneously. The SRX's brakes, though not embarrassing, again ranked last. The pedal felt comparatively spongy, and the stopping distances (341 and 122 feet) were respectable yet unremarkable.
Third Place: Cadillac SRX V8 AWD cont...
On the wet racetrack, the SRX behaved similar to the BMW: terminal understeer requiring slower entry in most corners. The Cadillac's all-wheel-drive system relies on three open differentials and a host of monitoring devices to manage wheelspin through selective brake application. When the system detects loss of traction at a wheel, a brake is applied to the spinning culprit and power is routed to the wheel(s) with traction.
The problem here was both front wheels weren't spinning, but skidding wide of our intended path. We suspect the SRX's all-wheel-drive system is designed for, and is better suited to, getting a driver out of a slippery or icy situation from a stop rather than enhancing at-speed racetrack performance.
The SRX is an eye-catching, comfortable, and fleet-footed luxo-cruiser. It boasts the largest second-row accommodations despite being the only one here with an optional third row of seats for a total of seven-passenger spaces.
The $1800 "UltraView" sunroof practically removes and stows the entire roof for a true open-air driving experience. Keep in mind the base price of the V-8 SRX doesn't include all-wheel drive. It's bundled with the $7145 Luxury Performance package (with the trick shocks and other equipment) or as a $1900 stand-alone option. Cadillac's claim of the SRX being a "performance utility" is backed up by its test-leading acceleration, with the rest of its grades falling midpack.
Second Place: Infiniti FX45
Infiniti likes to promote the idea that its FX45 provides the practicality of a sport/utility with the heart of a sports car. In essence it's correct. The front-midship chassis is based on the award-winning G35 Sport Sedan, and the 315-horsepower V-8 is derived from the powerful M45 and Q45 luxury sedans (the FX35 is powered by a 280-horsepower version of the V-6 out of, among others, the 350Z.) It turns out this is a solid place to start. Within this group, the FX feels the smallest and tightest and most dedicated to performance.
Last year, many criticized the FX for its harsh, stiff-legged ride on anything but smooth roads. Infiniti has addressed the firm suspension complaints, finding more compliance while giving up little athleticism in the 2004 model. In relative terms, the FX45's performance dropped by about one mph in the slalom and 0.02 g on the skidpad versus a 2003 we tested. Still, steering through the slalom at over 62 mph and clinging to the pavement at over 0.80 g is impressive for any vehicle, much less a sport/utility.
In a straight line, the FX45 was well-suited to go toe-to-toe with its competition. With the best power-to-weight ratio, it ran alongside the quick Cadillac up to about 60 mph where the SRX opened up a small lead. By the quarter mile, the FX maintained its second-place finish by a narrow margin over the Porsche and BMW. When it came to hitting the binders, the FX was clearly better than average with repeated stops from 60 mph under 120 feet, with the best taking only 115. Dedicated sports cars would brag about these brakes, and only the Porsche did better in this test.
Second Place: Infiniti FX45 cont...
At the racetrack, all this go and whoa translated into a 1:11 lap time, or two and three seconds better than the BMW and Cadillac, respectively. That's huge. The Infiniti made time where the others couldn't because it resisted the understeer that plagued the other two, and, as a result, the driver was allowed to go to wide-open throttle sooner. Rather than waiting for traction at the front, the FX maintained it throughout, and we were able to exploit the all-wheel drive sooner, pulling the vehicle out of the corners.
In the photos, you'll notice a difference in the understeering BMW and Cadillac as compared with the more stable Infiniti and Porsche. The FX45 uses clutch-pack-style all-wheel drive (as all four do to some degree), but the software is set up differently. Unlike with the X5 and SRX, we could feel the FX's front tires biting at the wet pavement under full throttle, allowing it to steer rather than push around a corner. This performance-software rationale translates into more controlled driving performance.
In a world of performance claims, the Infiniti FX45 lives up to the promises it makes. It goes, stops, and corners like a competent sport sedan, though its organic/mechanical styling isn't for everyone. Call it what you will, this is truly a performance-biased sport/utility. And despite a slightly confining cabin, it'll still hold far more stuff behind the seats than the BMW and Porsche. In this performance-weighted comparison, there's only one better.
First Place: Porsche Cayenne S
People either laughed or cried when Porsche announced it was going to build a sport/utility. They criticized the sports-car maker for acquiescing to the current demand for SUVs in the U.S., saying it just wanted to cash in. Well, we're here to tell you that Porsche did build its sport/utility, and currently there's nothing that can touch it on a racetrack.
With a lion-hearted 340-horsepower V-8, but a 5300-pound curb weight, the Cayenne needed to launch 15.6 pounds with each horse. As a result, it locked horns with the BMW and Infiniti in acceleration runs, each taking turns in the lead by a tenth here or there. The three tied at 17.3 seconds to 100 mph, where the incredible Cadillac was a full second quicker.
Stand on the brake pedal, however, and the Cayenne S stopped in less distance (111 feet) from 60 mph than a race-ready Porsche 911 GT3 (113 feet). From 100 mph, the two Porsches tied at 318 feet--astoundingly good brakes, and the FX45 was a couple feet longer.
Part of the credit for the Porsche's amazing stops goes to the optional Porsche Active Suspension Management, or variable damping system, which keeps the Cayenne as flat as possible under dive, squat, and roll conditions. Whether accelerating, braking, or cornering, the shocks continually adjust to firm up or smooth out and compensate for weight transfer. For instance, selecting the "Sport" shock setting from three PASM choices stiffens the damper settings. Even if the selector is left in "Comfort" or "Normal" position, the Cayenne S will detect aggressive driving and select "Sport" automatically, returning to its previous setting when appropriate. For the slalom test, we selected "Sport" and the second lowest allowable of six ride-height levels (the absolute lowest setting is for loading). The full range of ride height spans 4.5 inches with the optional air suspension.
The results of the shock firmness and height control (and really wide tires) translated to the quickest slalom speed in the test. In fact, at 63.2 mph, only a more expensive Cayenne Turbo (and last year's FX45) have ever posted a faster slalom speed for a sport/utility.
First Place: Porsche Cayenne S cont...
The neat part is that you don't have to drive it around town with these sporty settings. Click it over to "Comfort," and it rides nearly as smoothly as the Cadillac SRX. Drive like a rally driver, and the system automatically switches over to "Sport" and back again when you're done.
Porsche has decades of all-wheel-drive experience. From the legendary 959 to the current 911 Turbo, the Cayenne is only the latest Porsche to employ all four wheels under power. Like the rest of the sport/utes in this group, the Cayenne S uses a multiplate clutch to split drive forces front and rear (38 percent front and 62 percent rear in normal driving).
However, there's a significant difference in the Porsche. The clutch acts on a proper center differential, so it can shift up to 100 percent to either the front or rear axle, based on vehicle speed, lateral acceleration, steering angle, and throttle position--a unique feat among this otherwise similar group. The computer calculates the optimum locking required on both axles to distribute power to the front and rear as needed. The Cayenne knows when and where to put the power to go fast.
At the racetrack, we tried repeatedly to upset the Cayenne, make it push, slide, or do anything but track exactly where we pointed. As long as we had our foot firmly on the gas, it was nearly impossible to get the Porsche out of shape--even with the stability system defeated. There are sports cars that'd have a tough time making a 1:09 lap in the dry at the Streets of Willow, but the Cayenne did so in the wet. That's two seconds ahead of second place, four and five seconds ahead of third and fourth.
Anybody who had his doubts about the Cayenne's abilities was humbled. While it might not be the fastest in a straight line, throw some curves in front of the Porsche and things sort themselves out in a hurry. Our figure-eight test underscored this ability with the Cayenne's clearly superior run, which puts it solidly in the neighborhood of a Nissan 350Z Track model or an SVT Mustang Cobra.
The next time you wish you had a Porsche sports car but need an SUV (and have a stack of U.S. fund coupons or the requisite credit rating), there's one true performance utility that satisfies both criteria. Look no further than the Cayenne S to shame any wannabes--and a few sports cars as well.
| ||2004 BMW|
SRX V8 AWD
|Acceleration, sec to mph|
|1/4 mile, sec @ mph||14.9 @ 94.5||14.6 @ 96.3 ||14.8 @ 95.1||14.9 @ 94.9|
|Braking, 60-0 mph, ft ||119 ||122 ||115 ||111|
|Braking, 100-0 mph, ft ||336 ||341|| 320 ||318|
|600-ft slalom, mph||61.7|| 60.3||62.6||63.2|
|Wet course lap, min:sec||1:13||1:14||1:11||1:09|
|Figure 8, sec @ ave g||27.35 @ 0.63||28.00 @ 0.62||26.98 @ 0.66||26.36 @ 0.67|
|200-ft skidpad, g||0.76||0.76||0.82||0.86|
|Top-gear rpm @ 60 mph||1900||1800||2250||2000|
|On sale in U.S.||Currently||Currently||Currently||Currently|
|Base price incl dest||$52,795||$46,995 (V-8 w/rwd)||$44,965 ||$56,665|
|Price as tested||$60,295|| $58,140|| $53,835 ||$68,760|