Can You DIG It?
Powertrain trends include direct injection gasoline (DIG)
By Bill Visnic
Now in its 12th year, the annual Ward's 10 Best Engines competition continues as the industry barometer of powertrain development.
Although little has changed about the competition, itself, 2006's 10 Best Engines are evidence that meaningful change is enveloping the industry's powertrain sector.
First, four of the 10 Best Engines employ forced induction — a new record for the list. This is significant because it indicates a trend toward the downsized engines and higher specific output some powertrain analysts have predicted.
Certainly 2005's high-profile run-up in fuel prices increased the public's attention on fuel economy, but recent events that affected fuel prices could not have influenced the engineering development of the winning engines, which began years ago.
Forced induction — turbocharging, specifically — also is the “companion” technology to the powertrain sector's other emerging trend: direct injection gasoline (DIG) fuel delivery.
The number of DIG engine variants in North America and the rest of the world is quickly blossoming as the technology merges the attributes, to some degree, of spark-ignition and compression-ignition engines. Three of this year's 10 Best Engines feature DIG technology, and we expect more in the future.
For 2006, Ward's 10 Best Engines judges nominated and tested 31 engines that must be available in regular-production vehicles on sale in the U.S. market no later than the first quarter of 2006. To be eligible, the engine also must be available in a vehicle with a base price of no more than $52,500.
By limiting the competition to volume-market considerations, the annual 10 Best Engines awards have a high degree of relevance, we believe, to the majority of the industry's powertrain developers, as well as consumers.
How Important Is the Engine When Dealers Sell a Vehicle?
By Cliff Banks
Dealers differ as to the importance of the engine in the sale of a vehicle.
Engines are highly technical and their benefits can be lost on the buyer and even the salesperson. Yet the engine is the soul of the vehicle; it is what provides the car's character and feel. And depending on an auto maker's branding and marketing strategy, a great engine can make all the difference.
Customers have different wants and needs — it is not always about high horsepower, says Brian Marze, sales manager for Jim McNatt Dodge Toyota Scion in Denton, TX,.
“The fuel economy is important to the Toyota customer,” Marze says. “And so is reliability. The Toyota customer just wants to know that engine is going to last a long time.”
Dodge customers, on the other hand, often buy because of the Hemi engine, he says.
“That engine is a major part of the buying decision for them,” Marze says. “In fact, Dodge has a full line of engines from the Hemi — which is in several vehicles — to its diesels. Dodge has done a great job branding those engines.”
Denny Christian, dealer principal for Alan Christian Buick Olds Pontiac in Dexter, MO, says the engine's impact is not huge, “but customers do show interest.”
He adds, “I would say it's mostly younger people who come in and ask about the engine. But that's not always the case. We have a lot of older guys who seem more interested in an engine's horsepower.”
Other dealers, though, think the engine plays a minimal role in a customer's buying decision.
“I don't think there is a real impact,” says Todd Carriker, general manager for Carriker Ford, in Oskaloosa, IA. “If you think about it, Ford doesn't talk too much about their engines.”
Some customers do come into his showroom and talk about Ford's diesels, he says. Others, mostly farmers, look for an engine with towing capacity.
“Other than that, I don't think the engine is a big deal,” Carriker says.
Powerful and Frugal
Audi AG 2L FSI Turbocharged DOHC I-4
Some complain Audi AG's new A3 is too expensive for an entry-level luxury car.
Clearly, those critics are not powertrain aficionados, or else they would recognize an A3 starting at $24,740 is hideously cheap access to a technology-packed powder keg of an engine such as Audi's all-new 2L FSI DOHC I-4.
Like the 1.8L turbocharged 4-cyl. before it, the new mill combines the power density expected of a premium-class engine and the fuel economy that is virtually a requirement (at least in Europe) to compete in the segment's luxury/sport end. But Audi's new 2L I-4 improves greatly on the high standards set by the 1.8T it replaces.
While we miss the exotic 5-valve-per-cylinder configuration of the 1.8T, the 2L FSI makes up for its more-conventional 4-valve layout by sticking a fuel injector into the combustion-chamber, real estate that used to be occupied by Audi's signature fifth valve.
Engine type: 2L DOHC I-4
Displacement (cc): 1,984
Block/head material: iron/aluminum
Bore × stroke (mm): 82.5 × 92.8
Horsepower (SAE net): 200 @ 5,100-6,000 rpm
Torque: 207 lb.-ft. (280 Nm) @ 1,800-5,000 rpm
Specific output: 100 hp/L
Compression ratio: 10.3:1
Fuel economy for tested vehicle (EPA city/highway mpg): 25/31
Application tested: A3 2.0T
Torque You Very Much
Audi AG 4.2L DOHC V-8
The reasons Audi's V-8 returns for a third consecutive 10 Best Engines award are manifest, most having to do with the “character” said to be lacking from modern-day V-8s.
First, but probably not foremost, are the sounds. From the moment one fires it up until the key is twisted to shut down, this engine engulfs vehicle occupants in a 3-ring circus of aural delight.
Next, and probably foremost, is what must be the Audi V-8's official motto: “Torque: There is no substitute.”
And to us, nothing says “fine machinery” like a V-8 with a power peak of 7,000 rpm.
Finally, there is the price. The Audi 4.2L mill is one of the few premium V-8s that can be had in a vehicle with a base price (barely) less than the $52,500 10 Best Engines price cap.
Engine type: 4.2L DOHC 90° V-8
Displacement (cc): 4,163
Block/head material: aluminum/aluminum
Bore × stroke (mm): 84.5 × 92.8
Horsepower (SAE net): 340 @ 7,000 rpm
Torque: 302 lb.-ft. (409 Nm) @ 3,500 rpm
Specific output: 81 hp/L
Compression ratio: 11:1
Fuel economy for tested vehicle (EPA city/highway mpg): 15/21
Application tested: S4 sedan
BMW's Best Inline 6-Cylinder Yet
BMW AG 3L DOHC I-6
For the last two years, BMW's baseline I-6 architecture was out-powered by market-comparable V-6s. With 235 hp in its highest spec, the engine most closely associated with the Ultimate Driving Machine had fallen off the pace. Consider it a brief interlude in BMW's march to perfect its brand-defining inline 6-cyl. layout: The new, 12th-generation (N52) '06 3L DOHC I-6 is an unqualified gem.
There is a jump of 30 hp and a torque increase of 6 lb.-ft. over the previous-generation M54 3L inline mill. More telling, the new BMW I-6's specific output of 85 hp per liter now places it in the top tier of 6-cyl. power density, particularly now that some V-6s have endured a chopping of their output in the wake of new horsepower testing procedures. BMW's latest inline 6-cyl. is its best yet.
Engine type: 3L DOHC I-6
Displacement (cc): 2,996
Block/head material: magnesium-aluminum/aluminum
Bore × stroke (mm): 85 × 88
Horsepower (SAE net): 255 @ 6,600 rpm
Torque: 220 lb.-ft. (298 Nm) @ 2,750 rpm
Specific output: 85 hp/L
Compression ratio: 10.7:1
Fuel economy for tested vehicle (EPA city/highway mpg): 20/30
Application tested: 330i
Wipes Floor with Competition
DaimlerChrysler AG 5.7L Hemi Magnum OHV V-8
The Hemi's ongoing appeal runs much deeper than a fortuitous marketing re-connect with baby-boomers. The Hemi is about real power and real engineering.
There is skepticism that the modern-day 5.7L Hemi V-8, returning for its fourth consecutive 10 Best Engines win, really has hemispherically shaped combustion chambers that led to the original Hemi's name.
But in a sense, it's not that important. Chrysler powertrain engineers studied the gas-flow characteristics of some of the world's best-engineered and best-performing engines (including Porsche AG's power-dense horizontally opposed 6-cyl.) and came up with a design that shares many of the attributes of a hemispherical combustion chamber.
The rest is history. The Hemi's simple architecture, combined with smart design details, makes a powerhouse package that wipes the floor with the competition.
Engine type: 5.7L OHV 90° V-8
Displacement (cc): 5,654
Block/head material: iron/aluminum
Bore × stroke (mm): 99.5 × 90.9
Horsepower (SAE net): 350 @ 5,200 rpm
Torque: 390 lb.-ft. (529 Nm) @ 4,000 rpm
Specific output: 61 hp/L
Compression ratio: 9.6:1
Fuel economy for tested vehicle (EPA city/highway mpg): 17/25
Application tested: Dodge Charger R/T
No Slowing This Mustang Down
Ford Motor Co. 4.6L SOHC V-8
Associating this spectacular engine so closely with the Mustang is both boon and curse. It is an advantage because the Mustang owes its runaway success to its excellent, new-generation V-8.
Without it, enthusiasts would not have bought the 'Stang as the real deal, regardless of the car's brilliant sheet metal. But the engine's close affiliation with the Mustang discounts this outstanding modular V-8's keen work in its other high-volume home, the Explorer/Mercury Mountaineer SUVs.
The lightened flywheel encourages exploring the upper tach range, and the 4,500-rpm torque peak underscores the modular 4.6L SOHC V-8's newfound ability to rev to places the old 4.9L pushrod V-8 never visited.
Plus, this engine is perfectly happy to run on regular unleaded gasoline. No auto maker provides a more power-packed V-8 at a more accessible price than Ford's brilliant 4.6L SOHC V-8.
Engine type: 4.6L SOHC 90° V-8
Displacement (cc): 4,604
Block/head material: aluminum/aluminum
Bore × stroke (mm): 90.2 × 90
Horsepower (SAE net): 300 @ 5,750 rpm
Torque: 320 lb.-ft. (434 Nm) @ 4,500 rpm
Specific output: 65 hp/L
Compression ratio: 9.8:1
Fuel economy for tested vehicle (EPA city/highway mpg): 17/25
Application tested: Mustang GT
Like Firecracker In Mailbox
General Motors Corp. 2L Supercharged DOHC I-4
By winning a 10 Best Engines award in the first year of production for this engine, General Motors Corp. proves it can play ball in the performance market.
We can think of few options for a sophisticated, forced-induction DOHC 4-cyl. that fronts 100 hp per liter and can be had in a vehicle that starts at less than $22,000.
The 40% horsepower pop over the standard 2.2L mill comes largely from the ministrations of an Eaton Corp. M62 roots-type supercharger sending the intake charge through a unique air-to-water intercooler.
Crack open the throttle of the 2L supercharged Ecotec 4-cyl. and the firecracker-in-a-mailbox fun runs from idle through to the 5,600-rpm power peak.
The punch practically rushes out of this engine. It is the best compact-performance engine at its price and can stand against many engines in much pricier vehicles.
Engine type: 2L supercharged DOHC I-4
Displacement (cc): 1,998
Block/head material: aluminum/aluminum
Bore × stroke (mm): 86 × 86
Horsepower (SAE net): 205 @ 5,600 rpm
Torque: 200 lb.-ft. (271 Nm) @ 4,400 rpm
Specific output: 103 hp/L
Compression ratio: 9.5:1
Fuel economy for tested vehicle (EPA city/highway mpg): 23/29
Application tested: Chevrolet Cobalt SS
No Hope to Cure TME (Too Much Engine) Disease
By Bill Visnic
In addition to my day job, I'm the non-celebrity spokesperson for TME Disease.
Like Bob Dole for erectile dysfunction (ED), I have taken on the job of educating you about a disease ravaging the auto industry: TME, the acronym for Too Much Engine.
Auto makers afflicted with TME take perfectly good vehicles and wedge in engines that are too large or too powerful, frequently ruining vehicle dynamics.
TME can afflict any auto maker of any size and origin.
The most prevalent carriers of TME are misguided product planners and marketing dweebs, but technical types such as chief engineers also can spread the disease.
This year, as a result of a decade or more of ongoing horsepower battles in the U.S., there are widespread cases of TME.
General Motors Corp. was stricken several times with TME. Its Chevrolet Monte Carlo SS and Grand Prix GXP are Frankenstein's monsters thanks to the unholy fitment of a 5.3L small-block V-8 that drives the front wheels.
Moreover, drivers of these become afflicted with carpal tunnel syndrome, as their wrists strain in the vain attempt to control torque steer (that's a cause for another spokesperson).
Low-volume performance-division vehicles usually get a pass on this type of criticism because it is part of their mission statement to create insanely powerful engines.
They also usually have the budget and resources to reengineer the platform to a point where it can accommodate nutty levels of horsepower and torque. In the case of the BMW M5 and Audi S4 (one of our 10 Best Engines winners), it works out brilliantly.
But when auto makers try to drop big engines into less-modified chassis, it frequently becomes a disease that kills a vehicle's reflexes. Just because an idea works in a few applications does not make it a formula for success.
Audi AG suffers from TME with the A4. This otherwise wieldy and desirable compact sport sedan turns into a slug when the too-large 3.2L DOHC V-6 is installed without appropriate ministrations to the rest of the platform. Steering sharpness is destroyed, as is any semblance of balance.
Nobody supports righteous horsepower more than the people who annually bring you the Ward's 10 Best Engines awards, but power fever is affecting everyone's judgment: TME is everywhere.
How else to explain a Jeep Grand Cherokee with an iron-block 6.1L Hemi V-8 and 420 hp? Same for Porsche Cayenne Turbo and virtually every new Mercedes-Benz AMG vehicle.
Just because an engine can be crammed in does not mean it makes sense to do so.
There currently is no cure for TME. Sadly, precious product-development dollars are wasted every year to create vehicles with TME, money that could be used for better interiors and electronics that work.
Alas, critics believe TME likely never will be eradicated as long as there are customers afflicted with TMDI: Too Much Discretionary Income.
Hemi Is Bad and Proud of It
By Barbara McClellan
There's only one word for Chrysler's 5.7L and new 6.1L Hemi OHV V-8 engines: Sweet. The two were test-driven by Ward's this year in the '06 Charger and 300C SRT-8.
What else can you say about the 6.1L V-8 high-powered version of the much-lauded Hemi that hasn't been said about the 5.7L? Well, plenty actually. It's all about the numbers: 85 more ponies and 30 lb.-ft. more torque. Plus slightly better fuel economy!
This variant achieves its increased power mainly with displacement and revs. The cylinder bore is increased by 13 mm each, and the power peak is about 800 rpm higher. Meanwhile, all the internals are beefed up to accept the power and torque enhancement.
Those are the tangibles, but the esoteric value is in the driving experience. This enhanced engine makes the wide-body 300C feel light as a feather. Acceleration is seamless and seemingly endless.
Forget the oversized steering wheel, the lost-in-space cabin and huge toothy front grille. Close your eyes and you're in the sleekest and nimblest of sports cars.
Despite the engine's propensity for sucking fuel, hordes of Hemi fans appear unfazed. The auto maker in reported the take rate for the 5.7L V-8 was steady at a 43% average for all the vehicles in which it is available.
As a result, Chrysler is escalating the rollout of its fuel-saving Multi-Displacement System (MDS) cylinder deactivation technology, which shuts down four of the Hemi's cylinders when their output is not needed.
Generating as much as a 20% reduction in fuel consumption, MDS is featured on about 85% of all the 5.7L Hemi V-8s produced, except for those units destined for heavy-duty applications.
Chrysler builds about 500,000 Hemi engines annually. Hemi means “power.” It means “special.” It means “bad and proud of it.”
Rare and Satisfying Format
General Motors Corp. 2.8L Turbocharged DOHC V-6
The dominant engine layout in the U.S. is the V-6. Strangely, though, few use forced induction to generate big performance. In the U.S., if you want a V-6 with better performance, you buy a V-8.
So it is a special day to see this all-new turbocharged V-6.
It has such an engaging all-around performance profile, we wonder why more auto makers do not take a chance on this rare and satisfying format.
The low-ish torque figure of 258 lb.-ft. betrays this engine's comparatively diminutive displacement. But what it lacks in ultimate thrust is compensated for by the delectable torque curve typical of a turbo engine: Every pound-foot of twist is at your disposal from just 2,000 rpm.
On the road, that translates into flexibility normally aspirated V-6s and V-8s cannot replicate.
Engine type: 2.8L turbocharged DOHC 60° V-6
Displacement (cc): 2,792
Block/head material: aluminum/aluminum
Bore × stroke (mm): 89 × 74.8
Horsepower (SAE net): 250 @ 5,500 rpm
Torque: 258 lb.-ft. (350 Nm) @ 2,000-4,800 rpm
Specific output: 89 hp/L
Compression ratio: 10:1
Fuel economy for tested vehicle (EPA city/highway mpg): 18/28
Application tested: Saab 9-3 Aero
High Performance, Low Cost
Mazda Motor Corp. 2.3L DISI Turbocharged DOHC I-4
Few hoods in the U.S. market cover a hotter engine that costs less. This 4-cyl. pounds out a Ferrari-like 119 horsepower per liter, but the Mazdaspeed6, in which it serves as the standard engine, costs less than a tuneup for a Ferrari.
Thanks to the complimentary technologies of direct injection gasoline (DIG) — Direct Injection Spark Ignition (DISI) in Mazda-speak — and turbocharging, this engine is quieter, has less spastic throttle response and presents a broader power band than the stun-grenade 4-cylinders of its Japanese rivals, whose engines, by comparison, constantly bark like a riverboat captain.
While most non-DIG turbocharged engines wallow at low speed, waiting for their turbos to wind up, the new DIG turbo mills snap to attention directly from idle. When the torque benefits of DIG are bleeding off at higher rpm, the turbocharger already is making efficient boost. Magnificent!
Engine type: 2.3L turbocharged DOHC I-4
Displacement (cc): 2,260
Block/head material: aluminum/aluminum
Bore × stroke (mm): 87.4 × 94
Horsepower (SAE net): 274 @ 5,500 rpm
Torque: 280 lb.-ft. (380 Nm) @ 3,000 rpm
Specific output: 119 hp/L
Compression ratio: 9.5:1
Fuel economy for tested vehicle (EPA city/highway mpg): 19/25
Application tested: Mazdaspeed6 GT
The Hybrid Honeymoon Is Over
By Drew Winter
Iarsh reality is settling in. After winning 10 Best Engines awards in 2004 and 2005, no hybrid electric vehicle (HEV) powertrain made our list this year. Chalk it up to rising expectations and a declining gee-whiz factor.
In other words, our honeymoon with hybrids is over.
Environmentalists say HEVs are the magic bullet that will save the auto industry as well as the atmosphere. Auto makers are charging hefty premiums for the technology. In that light, the HEVs we tested this year are as good as ever, but not living up to their own hype.
We have been duly impressed in the past, naming Toyota Motor Corp. HEVs to the 10-Best Engines list twice and Honda Motor Co. Ltd.'s system once.
In 2001, we were thrilled with the way Toyota brought HEV technology to the practical Prius sedan in a relatively transparent fashion. In 2004 we were awed by how much Toyota improved the system.
Last year, judges were wowed by the way Honda's sophisticated Integrated Motor Assist (IMA) hybrid system dispelled the myth that HEVs have to be slow and boring.
This year we could not ignore a few shortcomings.
First among our complaints, pointed out by a growing number of disgruntled owners, is real-world fuel economy far less than what is advertised.
Second, fuel economy is affected too much by driving style and ambient temperature.
The Lexus 400h is the epitome of luxury and environmental friendliness when we moved silently through stop-and-go traffic on full electric power. But once the vehicle's internal combustion engine gets involved with propulsion, we were less impressed. During hard acceleration it doesn't have the premium sound we expect from a vehicle with a base price approaching $50,000. Plus, we were underwhelmed with our 25 mpg average.
NASA astronaut Ken Mattingly spent tedious hours in a flight simulator figuring out a start-up sequence that used only 20 amps for an energy-starved Apollo 13. That made for compelling drama in a movie.
Employing the same power-saving tactics just to squeeze out something close to the EPA mileage from a Civic Hybrid on a cold day is a bit less engaging.
Want something close to its alleged 49/51 mpg on a frosty morning? Forget about warming up the engine or using the defroster. Scrape the windows by hand, stay off the throttle and the expressway and get ready to shiver.
Enduring that kind of inconvenience is fine if you need to get back from space with your fuel cells spent, but not when you're just heading to work.
Unprecendented 12-for-12 Win
Nissan Motor Co. Ltd. 3.5L DOHC V-6
An engineer for one of Nissan Motor Co. Ltd.'s rivals recently groused, “You know, you really ought to call it ‘Ward's 9 Best Engines,’ because Nissan automatically gets a win every year.”
The comment was offered good-naturedly but with a twinge of frustration.
With a record 12th consecutive win for its landmark 3.5L VQ DOHC V-6, Nissan is making a case for the engineer's suggestion.
It has been a 10 Best Engines winner every year for some variant of Nissan's fabulous VQ engine family since the competition began in 1995.
In a dozen years since the launch of the original 3L VQ DOHC V-6, Nissan has wrought numerous improvements and changes.
There has been the addition of electronic throttle control, variable valve timing and two major new variants: the 3.5L that for some years has been the smallest-displacement VQ V-6 for the U.S. market and a more recently added 4L unit employed in the company's light trucks and SUVs.
Engine type: 3.5L DOHC 60° V-6
Displacement (cc): 3,456
Block/head material: aluminum/aluminum
Bore × stroke: 95.5 × 81.4
Horsepower (SAE net): 298 @ 6,400 rpm
Torque: 260 lb.-ft. (353 Nm) @ 4,800 rpm
Specific output: 85 hp/L
Compression ratio: 10.3:1
Fuel economy for tested vehicle (EPA city/highway mpg): 19/26
Application tested: Infiniti G35 6MT
First of a New Generation
Toyota Motor Corp. 3.5L DOHC V-6
This all-new Lexus engine, a first-time 10 Best Engines winner, is one of Toyota's first of a new generation to use direct-injection gasoline (DIG) technology, which company engineers say will be a cornerstone of the Lexus brand's initiative to be a powertrain-technology leader. In the coming years, all Lexus gasoline engines are to employ direct injection.
Using a novel new system that combines DIG and port fuel injection, the engine generates 306 hp, leading the class of premium V-6s. Its stout horsepower exceeds that of some well-regarded V-8s.
The direct/indirect fuel-injection system also delivers laudable fuel economy and an Ultra-Low Emissions Vehicle rating.
The complex top end is an elegant addition to the already excellent new port-injected DOHC V-6 architecture used in many Toyota-brand models.
In addition to the innovative fueling system, the new V-6 uses a host of other high-tech components, such as a unique plastic water-jacket spacer that prioritizes coolant for the upper block to reduce cylinder-head temperatures.
Engine type: 3.5L DOHC 60° V-6
Displacement (cc): 3,456
Block/head material: aluminum/aluminum
Bore × stroke (mm): 94 × 83
Horsepower (SAE net): 306 @ 6,400 rpm
Torque: 277 lb.-ft. (376 Nm) @ 4,800 rpm
Specific output: 87 hp/L
Compression ratio: 11.8:1
Fuel economy for tested vehicle (EPA city/highway mpg): 21/28
Application tested: Lexus IS 350
So Long Top Gun, Hello Luxury
By Cliff Banks
Saab Cars is reviving its aviation heritage in its latest television commercials, with images of the 9-3 Aero speeding as a formation of fighter jets zooms overhead, so I grabbed a flight jacket and my aviator glasses and climbed into the cockpit.
First, the 9-3 Aero with its 2.8L turbocharged DOHC V-6 is more like an upscale Gulfstream G550 executive jet than one of the fighters depicted in the commercials. So long Top Gun and hello luxury.
However, if you want to do some high-performance flying, just let the 9-3's engine spool up past 3,000 rpm.
This all-aluminum V-6 is new to Saab this year and is the latest member of General Motors Corp.'s global V-6 family, which includes the 3.6L in the Cadillac CTS.
But the turbocharged variant is unique to Saab.
Frankly, this engine's composed and sophisticated performance surprised this year's judges as it politely edged its way onto the 10 Best Engines list — with little argument, I might add.
Some engines stake their claim with brute power, while others do so with inventive technology.
The beauty of the 9-3's turbocharged V-6 is its smooth power delivery — a vast improvement over Saab's earlier and temperamental 4-cyl. turbo mills.
There are few engines as refined and pleasant as this one. Cycling through the gears, the expected whiff of turbo lag is almost nonexistent, as the peak torque of 258 lb.-ft. is available from 2,000 all the way to 4,800 rpm.
Meanwhile, the engine serenely delivers torque as it revs to an assertive 250-hp threshold, aided by the turbocharger's unique twin-scroll architecture with separate tracts that funnel the exhaust pulses emanating from each cylinder bank. That divides the job of spinning the turbine, reducing lag while increasing boost.
Another feature cool enough to be implemented across other GM brands is the jets that squirt oil onto the pistons to keep them from running too hot.
