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Making Horses - and Using Them '99 drivetrain advances are as much about using horsepower as making it

Drivetrain development has reached a fascinating new plateau.First, nobody's suggesting anymore (with the possible exception of Toyota Motor Corp.) that electric or hybrid vehicles will be a significant force in the car business for a number of years.Powertrain engineers from all over are asserting the new empowerment of internal-combustion engines: electronic controls are evolving to new levels of

Drivetrain development has reached a fascinating new plateau.

First, nobody's suggesting anymore (with the possible exception of Toyota Motor Corp.) that electric or hybrid vehicles will be a significant force in the car business for a number of years.

Powertrain engineers from all over are asserting the new empowerment of internal-combustion engines: electronic controls are evolving to new levels of sophistication almost on a weekly basis, permitting previously unimaginable mechanical miracles. Engine developers are extracting more horsepower - while using less fuel and spewing fewer emissions - than ever before.

And we're witness to similar achievements in the rest of the drivetrain: advanced transmissions incorporating a remarkable array of functions and, thanks to the sport/utility vehicle (SUV) explosion, an all-out renaissance in all-wheel-drive development - for both light trucks and passenger cars.

Chrysler Corp., for one, shows up for '99 with a formidable one-two punch in its new Grand Cherokee. To begin with, the '99 Grand has an all-new, SOHC 4. 7L V-8 that instantly outclasses the old 5.2L and 5.9L OHV V-8s previously used in the Grand Cherokee - as well as throughout the Chrysler light-truck lineup. It's built in a brand-spanking-new plant in Detroit, and you could eat off the floors and probably dine on the flexible machining tools, too.

Besides the move to an overhead-cam design, the new aluminum-headed Chrysler 4.7L has innovatively built hollow camshafts, magnesium valve covers and a thermoplastic intake manifold, all adding up to less - 52 lbs. (24 kg) less than the all-iron 5.2L V-8. Weighing and consuming less (Chrysler claims 20 mpg [11.8L/100 km] combined versus the 5.2's 17 mpg [13.8L/100 km]), the new 4.7L nonetheless enjoys a specific output of 49 hp/L, a significant jump over the old 5.2L's 42.3 hp/L.

This newly found horsepower gets to the ground first through an all-new 4-speed electronically controlled automatic that thinks, sometimes, that it's a 5-speeder. Yes, the 45RFE has but four true forward ratios, but for certain kick-down situations, a taller, 1.50:1 alternative second-gear jumps in rather than the normal-acceleration 1.67:1 second gear, the goal being to minimize engine noise and rpm when a less-violent downshift is warranted.

Finally, Jeep's got a whiz-bang new all-wheel-drive setup: Quadra-Drive.

Quadra-Drive is an all-mechanical system of so-called gerodiscs in both the transfer case and front and rear axles; in concert, the gerodiscs quickly transfer torque from spinning wheels to those on solid ground.

As torque builds up from a spinning wheel on one side of the Gerodisc pump the energy activates clutches on the other side of the axle to transfer traction to the other wheel. Another Gerodisc in the transfer case handles the same kind of transfer of engine power from front to rear.

The system can shift 100% power to any one wheel if necessary. No other system can currently make that claim, Chrysler engineers proudly explain. Competitors, like the Mercedes-Benz ML320 and the Lexus RX300 just slip and slide their way along, using a traction-control-based arrangement to limit torque to slipping wheels.

But Chrysler has only a thin hold on the Gerodisc technology that is so key to the performance of it's new Grand Cherokee.

It has exclusive rights to the Gerodisc in the transfer case, through New Venture Gear, for only one year. And the automaker's deal with Dana Corp. for the gerodisc system at each axle, sold as Vari-Lok on the Grand Cherokee, is almost identical.

Dana and NVG both license the system from California-based Asha Corp. Chrysler helped set up the deals so it could apply the technology to the new Grand Cherokee. But both suppliers are free to supply the technology to other automakers once their exclusivity ends, says Jack McCormack, Asha chairman and chief executive officer.

"The industry really is changing. (Automakers are) really moving away from just about anything but engines as their core," he says.

So far, only Dana, NVG and Steyr-Daimler-Puch have signed license agreements with Asha, he says. Others are under study.

Also sporting increased SUV power for '99 is Ford Motor Co. Both of the Expedition's Triton SOHC V-8s get a pony bump; for 4.6L models, from 215 hp to 240 hp, while the 5.4L Triton is upgraded from 230 hp to 260 hp. Each engine churns out more torque, too.

But watch out for the mid-'99 Navigator, as it switches from the 5.4L single-cam Triton engine to the snarly, dual-cam Intech 4-valve engines. Horsepower leaps to a not-insignificant 300, about the top you can expect from a luxury sedan these days.

Dan Kapp, Ford Power-train's manager of 5.4L engine development, hinted earlier this year that the newly muscled 5.4L Triton in the F-Series pickup had "implications for other product lines." Little did we know that his group's tweaking of the intake cam, reworking of the cylinder head and increase of exhaust-valve diameter would mean such significant gains for the Triton range - or signal such a serious boost for the Navigator's Intech DOHC engine.

Ford also has found 30 more hp for the hoary, 160-hp 3.8L OHV V-6 in the Mustang; 190 hp, special pistons and a fancy split-port intake now seems much more fitting as entry-level power. Meanwhile, the '99 Mustang's 4.6L V-8 is injected with an also-more-appropriate 25 new horses, for a total of 240 hp, achieved with some of that cylinder-head learning mentioned above.

We spoke at length recently about GM's significant addition to its 6-cyl. lineup, Oldsmobile's new 3.5L Twin Cam adapted from the Aurora/Northstar DOHC vee architecture (see WAW - Aug. '98, p.61). We'll have to wait to see where GM plans to next deploy the engine, but we're hearing Buick's name tossed around. And don't forget '99 brings the advent of the newly powered-up Vortec V-8s for the new Chevrolet/GMC pickups.

BMW AG is monkeying around significantly with its engine lineup for '99. In a move meant to enhance BMW AG's performance-oriented brand image, BMW North America executives reveal that the newly launched '99 3-series sedans will be sold in the U.S. only with the company's renowned inline 6-cyl. engines. Four-cyl. 3-Series cars gradually will fade away as BMW replaces them with 6-cyl. cars off the new Three's platform.

Apart from the move to all-aluminum construction, the new 3-series' 2.5L and 2.8L engines now employ BMW's VANOS infinitely variable valve timing system for both intake and exhaust valves. The system is dubbed Double VANOS, and BMW claims it substantially bulks up low- and mid-range torque.

Buyers of Honda Motor Co. Ltd.'s Acura TL won't complain when they see the new '99 TL (nee Vigor) comes with an all-new, 3.2L version of the all-aluminum 3L SOHC V-6 launched in the Accord. With 225 hp, the new 3.2L actually outpowers the 210-horse 3.5L DOHC V-6 Acura stuffs in the flagship RL. Explain that please, Acura.

Besides now being a real, 60-degree unit as opposed to the 90-degree job in the outgoing TL, the new engine is transversely mounted, as Acura apparently is done with its longitudinal-mounting experiment.

Mercedes-Benz says '99 is "the year of the V-8," and it's not kidding. You name it, the Germans are stuffing a V-8 in it. All units are based on the excellent, twin-spark, 3-valve-per-cylinder design Mercedes first showed in its V-6 range for 1997.

You'll find 4.3L V-8s in the M-Class SUV, the E-Class midliner and even the CLK coupe. The least these super V-8s deliver is 275 hp in the ML430 and CLK430; a heavily reworked version makes 302 hp in the gnarly, AMG-modified C43, while a really reworked, 5.5L unit gives up 349 orbit-velocity horses for the ultra-special, ultra-expensive E55 AMG.

And sometime in the '99 calendar year, look for another innovative method for getting power to all four wheels, this time from Volkswagen AG. Scary as this sounds, we understand VW plans to stay with the same 4Motion name under which this system was launched in Europe.

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