Booming Power For Boom Times

Automotive Industries,  March, 2000  

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The trend in light trucks is smaller V-8s with higher specific output.

The new round of emissions standards coming in 2004 to 2007, and the continued rumblings of higher CAFE, are putting a premium on greater specific output, particularly in trucks. The industry's 10-year gradual increase to larger displacements, driven by the light truck boom, is leveling off for both the traditional domestics and their "foreign" competitors (see chart).

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This year's Engine Trend charts again focus on torque output, as that's what drives the vehicle. Popular V-8s in coming years will be sub-5.0L, and calibrated to produce torque in the 300 to 330 lb-ft range. Higher revving than the domestics' traditional ohv V-8s, the BMW, Toyota/Lexus and Mercedes V-8s noted below are the first wave of these new powerplants. The domestics are planning to counterattack soon with their own new breed, including three-valves-per-cylinder heads on the Ford 5.4L, DaimlerChrysler's 5.3L ohv, dual spark plug Hemi (see p.22), and aluminum-block GenIV versions of GM's famed "small block." They'll be the torque of the town.

When A/first launched Engine Trends in the late 1980s, engines built by Japanese and European OEMs were heads above the U.S. Big 3 in terms of specific output - horsepower and torque per liter. But as the charts on this page show, that trend is changing. More higher revving, multivalve 4- and 6-cylinder designs are replacing the old guard, bringing the fleet averages much closer to their rivals.

Due to the truck segment and more rigorous safety standards, vehicles are getting heavier again. Since the downsized days of 1981, the average vehicle has gained 550 pounds. It now weighs 3,760 pounds, versus 3,201 pounds. But additional power has overcome the extra mass, as evidenced by average 0 to 60 mph times: 10.8 seconds today, versus 14.4 seconds in '81.

It all spells progress, except that over the same period, total fleet (cars and trucks combined) fuel economy has fallen to 23.8 mpg - the worst since Ronald Reagan was inaugurated.

"Market survey after market survey tells us environmental issues are increasingly important to our customers," noted General Motors Vice Chairman Harry Pearce in a recent interview. It appears that Japanese automakers are taking that trend more seriously, based on who's offering the cleanest gasoline-powered cars this year. Honda and Nissan become the first automakers to introduce SULEV - Super Ultra-Low Emission Vehicles - with the 2000 Accord EX and Sentra CA. Other "top cleanest" cars are Ultra Low Emissions (ULEV) rated. They include Honda's LX and EX 4-cylinder Accords and Insight gasoline-electric, Toyota's Camry sedan and coupe, and 4-cylinder versions of Mazda's Protege (1.6L) and 626 (2.0L). The Chrysler and Dodge Neon 2.0L is also a ULEV.

The SULEV category, recently adopted by the California Air Resources Board, goes into effect in 2004. It's even more stringent than ULEV. A SULEV emits slightly more than two pounds of hydrocarbons during 100,000 miles of driving -- an 80 percent reduction over the current LEV levels. Oxides of nitrogen (NOx), the prime ingredient in smog, are about 75 percent less. Emissions from a vehicle that meets SULEV are said to be equal to those from a pure electric car, operated on electricity generated by a typical power plant.

To meet SULEV with the Sentra engine, Nissan utilizes a trio of three-way catalysts, with three [O.sub.2] sensors between them. The two downstream cats also serve as hymn traps. The car's radiator is coated with Englehard Corp.'s PremAir catalyst, which earns it one-fifth of an emission credit normally given to a zero-emission electric vehicle. (See p. 25; also Feb. '00 AI, p. 95). Honda's SULEV Accord gets the same partial ZEV credit.

To achieve both SULEV and ULEV, Honda and Nissan had to double the palladium content of the car's underfloor catalytic converters. The rapidly rising price of palladium and other precious metals used in exhaust catalysts has automakers concerned. Palladium's price has risen nearly 300 percent since 1997, due to booming auto demand and uncertainty in the Russian market. Russia accounts for over 70 percent of the world's palladium reserves. A recent report by Reuters notes that metals futures analysts are predicting palladium's price could top $700 per ounce this year. Experts say skyrocketing prices could reverse the industry trend toward using palladium in catalytic converters back to platinum, while raising automakers' cost in meeting LEVII and Tier2 standards. Catalytic converters require more palladium than platinum to have the same effect.

TOP FIVE SPECIFIC-TORQUE V-8s (lb - ft per liter)

Make                                     BMW
Displacement (L)                        4.4L
Valvetrain                              Dohc
Valves/cyl                                 4
HP@rpm                             282@5,400
Torque (lb-ft)@rpm                 324@3,600
Specific Torque                73.2 lb.ft./L
Specific HP                           64.0/L
Vehicle                                   X5

Make                          Toyota (Lexus)
Displacement (L)                        4.7L
Valvetrain                              Dohc
Valves/cyl                                 4
HP@rpm                             230@4,800
Torque (lb-ft)@rpm                 320@3,400
Specific Torque                68.0 lb.ft./L
Specific HP                           48.9/L
Vehicle                        Land Cruiser,
                               Tundra, LX470

Make                           Mercedes-Benz
Displacement (L)                        4.3L
Valvetrain                              Sohc
Valves/cyl                                 3
HP@rpm                             268@5,500
Torque (lb-ft)@rpm                 288@3,000
Specific Torque                       66.9/L
Specific HP                           62.3/L
Vehicle                                ML430

Make                          Ford (Lincoln)
Displacement (L)                        5.4L
Valvetrain                              Sohc
Valves/cyl                                 4
HP@rpm                             300@5,000
Torque (lb-ft)@rpm                 355@2,750
Specific Torque                       65.7/L
Specific HP                           55.5/L
Vehicle                            Navigator

Make                              Land Rover
Displacement (L)                        4.6L
Valvetrain                               Ohv
Valves/cyl                                 2
HP@rpm                             222@4,750
Torque (lb-ft)@rpm                 300@2,600
Specific Torque                       65.2/L
Specific HP                           48.2/L
Vehicle                          Range Rover