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2000 NAIAS: GM Precept concept

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Let's go back to the future...

GM Unveils Concept Car That Gets 108 Miles A Gallon

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PRECEPT IS LATEST CHAPTER IN GM'S CONTINUING STORY OF ADVANCED CLASS VEHICLES

DETROIT - January 11, 2000 - General Motors Corp. (NYSE: GM) today unveiled the Precept advanced class vehicle, in both hybrid and fuel cell powered forms, at the North American International Auto Show at Detroit's Cobo Center. The Precept is the latest demonstration of GM's capability and commitment to building vehicles that will ultimately help to remove the automobile from the environmental debate.

The Precept is an example of the type of ultra-high-efficiency architecture that GM is developing on its way toward putting millions of environmentally friendly vehicles on the road. The key to GM's advanced vehicles strategy is to focus on a number of options for clean transportation solutions, not just one.

The parallel-hybrid Precept uses the most aerodynamically efficient design in the world, with a drag coefficient (Cd) of 0.163, 20 percent less aerodynamic drag than the production record-holder, the GM EV1 (0.19). Its four-wheel drive, dual-axle set-up features a 35kW three-phase electric motor driving the front wheels and a lean-burn compression-ignition, direct-injection (CIDI) heat engine driving the rear wheels.

CONTACT: Jeff Kuhlman

PHONE: 248-680-5999

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General Motors Vice-Chairman Harry Pearce poses next to the Precept, a fuel cell powered vehicle, that breaks the 100 mile-per-gallon barrier with a stunning 108mpg. The Precept was introduced at the 2000 North American International Auto Show in Detroit 1/11. The Hydride Hydrogen storage system can deliver up to a 500 mile range.

January 1, 2000 - REUTERS

General Motors Corp. Saturday unveiled an experimental, teardrop-shaped sedan called the Precept, which is capable of getting 80 miles per gallon. The GM Precept, an experimental sedan built by General Motors Corp. travels about 80 miles on a gallon of gasoline.

Both the five-passenger Precept and the Prodigy by Ford Motor Co. will make their official debuts at the North American International Auto Show in Detroit, which opens to the media on Jan. 9. Ford provided the first glimpse of the Prodigy, which gets more than 70 miles per gallon, on Dec. 29.

The cars were developed under the federally sponsored Partnership for a New Generation of Vehicles (PNGV). Members of the industry-government collaboration, launched in 1994, are committed to building by 2004 production-ready prototypes that can offer triple the fuel economy of a typical family sedan without sacrificing performance.

Company officials say the Precept and Prodigy will probably never go into mass-production because of their high costs. But some of the advanced fuel-economy technology could wind up in consumer-ready cars and trucks.

"Eighty miles per gallon really pushes you to the edge of the envelope," said Robert Purcell, executive director of GM's Advanced Technology Vehicles. "Pieces of what we've got in Precept could find their way into production vehicles."

The hybrid-electric Precept is driven by a battery-powered electric traction system that moves the front wheels, and a lightweight, 1.3-liter, 3-cylinder diesel engine in the rear. The direct-injection engine, featuring turbocharged compression ignition, was developed by Isuzu Motor Co. Ltd., one of GM's Asian affiliates.

GM has developed the electric motor to run off either a nickel metal hydride battery, like the kind used in the new version of its EV1 electric car, or a lithium polymer battery. The electric traction system also captures energy from braking and sends it back to the battery.

Designers of the Precept took their overall design cues from the EV1 and constructed the car to be as aerodynamic as possible. Exterior door handles have been eliminated, and outside mirrors were replaced by a camera system. Because front-facing grills create wind drag, the Precept has special air

openings behind the rear wheels.

The Ford Prodigy also has cameras instead of side-view mirrors. It has a more conventional look, featuring a body style similar to some luxury cars made by Germany's Audi.

The Prodigy, based on the P2000 LSR that Ford introduced in October, uses a 1.2-liter, 4-cylinder diesel engine and nickel-metal hydride battery. Use of lightweight materials such as aluminum and titanium have brought the car's weight to 2,387 pounds, about 1,000 pounds less than a modern family sedan.

"The vehicle represents an interim stage between our P2000 research programs and the development of an affordable, production hybrid in 2003," said Neil Ressler, Ford's vice president of research and vehicle technology.

The U.S. government is estimated to have spent about $240 million on PNGV projects last year. GM, Ford and DaimlerChrysler AGspent close to $1 billion, industry officials estimate. DaimlerChrysler will not show a PNGV vehicle at the Detroit auto show, but is on track to have one ready to meet the 2000

concept timetable.

All content © copyright 2000 Knight Ridder Inc. and may not be republished without permission.

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Car and Driver's review of DCX's Dodge ESX3 back in 2001:

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The real story of DaimlerChrysler's PNGV entry can be summed up in one word: plastics. Although the Metalcrafters shop in California built the concept car pictured here from hand-formed aluminum to save tooling costs, engineers designed the unitized body shell to come together from just 12 plastic moldings like a SnapTite model of the Charlie's Angels van. Aluminum tubes bonded internally to the plastic, what engineers have dubbed the "sparse frame," would keep the polymer pieces from wobbling. Some cavities would be filled with thermoset polyurethane foam braced by steel reinforcements. DaimlerChrysler honchos have whiled away many an hour daydreaming about such cars assembled from a few large pieces of injection-molded thermoplastic. The benefits: cheap tooling, the potential to mold in color so there is no expensive paint shop, and a low resulting weight. A plastic car such as the 2250-pound ESX3 could pop out of the molding 46 percent lighter than an equivalent steel job and 15 percent cheaper, says DaimlerChrysler.

The ESX3 in mass production would cost only a claimed $7500 more than today's Dodge Intrepid, due mainly to the extra cost associated with the hybrid powertrain. And DaimlerChrysler claims 80 percent of the car could be recycled, perhaps into an S-class cup holder. Detroit Diesel took a break from building 3300-hp tugboat engines to create the ESX3's 1.5-liter, three-cylinder direct-injection turbo-diesel. The 74-hp pipsqueak features an aluminum block and head, weighs in at just 249 pounds, and redlines at a lazy 4200 rpm. Even with its variable-geometry turbocharger, it wouldn't pull the cheese off a cold pizza without help from the 20-hp air-cooled Delphi flywheel-type electric motor sandwiched between the crankshaft and the six-speed manual transaxle. The gearbox, which is shifted automatically by the computer, accepts power via twin clutches that work in tandem to smooth over the big torque holes inherent in clutched transmissions. We took a brief run around a nearby park, and the fancy transmission acquitted itself best during hard acceleration, when shifts were their smoothest.

The ESX3 feels more ponderous than one would expect for a car weighing 10 pounds less than a Toyota MR2 Spyder, in part because the ultra-hard prototype Goodyear Eagle tires provide low rolling resistance but offer little bite in the corners. The regenerative brakes feel almost normal, unlike some hybrids whose nonlinear binders grab too hard too early. Pressure in the electronically managed turbo seems to build quickly and with no discernible lag. DaimlerChrysler claims a 0-to-60-mph time of 11.0 seconds, a number we were not able to validate but have no reason to doubt. As in the Honda Insight, the motor never operates solo. It provides motive assistance during acceleration, generates power for the battery pack, and restarts the engine after idle shutdowns. Regenerative braking helps keep the 106-pound, 165-volt, 1.0-kilowatt-hour lithium-ion battery pack topped off. Plastic isn't a panacea. Problems remain, including the fact that you can have any color as long as it is flat. And do you remember what happened when your Charlie's Angels van rolled off the table? Plastic doesn't deform predictably like metal. The 2001 Jeep Wrangler's one-piece plastic hardtop proves DaimlerChrysler is still interested in injection-molding large pieces for mass production, but it isn't clear where this initiative will go now that English is the second language in Auburn Hills.

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Ford Prodigy

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The name means "an extraordinary thing or person that inspires wonder," but the face just inspires a midafternoon nap. Ford actually intended the Prodigy to be plain. How better to convince the citizenry that the mysterious black boxes and miles of high-tension cables lurking under the skin are harmless? It also happens that the Prodigy's shape is pretty clean, cleaving the air with just a 0.20 drag coefficient. The Prodigy is a rebodied version of Ford's series of P2000 prototypes. These are roughly patterned after the out-of-production Ford Contour but stretched to meet the PNGV benchmark for interior space and constructed from aluminum stampings, extrusions, and die castings. Laden with the extra burden of batteries and a diesel-electric hybrid powertrain, the Prodigy's curb weight is still just 2400 pounds, about 350 pounds lighter than the base Contour. Engineers shaved weight wherever they could, using magnesium-framed seats and lightweight brake rotors, for example.

The 1.2-liter, four-cylinder direct-injection turbo-diesel goes by the name of DIATA, which stands for "Direct Injection Aluminum Through-bolt Assembly." It refers to the brace of lengthy bolts that stretch from the top of the engine to the oil pan to firmly clamp the aluminum head and block together. Ford developed the 74-hp unit's low-friction components together with German engineering consultant FEV Engine Technology but has already abandoned the through-bolt design for lighter and more elegant architecture. As in the ESX3, the Altoids-shaped electric motor rides between the flywheel and computer-shifted MTX75 five-speed gearbox from the Contour, the automatic clutch being integrated with the motor's central rotor. The three-phase AC induction unit can make up to 47 horsepower for three seconds but more often runs at a low 4-to-11 horsepower. It does triple-duty as engine starter, acceleration assistant, and power generator for the 288-volt, 1.1-kilowatt-hour nickel-metal hydride battery pack. But the Prodigy, like the ESX3 and Honda Insight, is a "low storage requirement" hybrid, meaning that it never relies solely on its electric motor for forward thrust. The best diesels today make less traditional diesel racket, thanks to the ability of direct-injection systems to allow multiple squirts of fuel for more gradual, and thus quieter, pressure buildup in the cylinders. This has a negative impact on fuel economy--about 2-to-3 mpg--which is why the Prodigy doesn't use it and thus sounds pretty much like a tow truck. As soon as you take your foot off the brake, the engine clatters to life (it only stays lit with your foot on the brake if you have the air conditioning set on max).

The powertrain we experienced in an early P2000 mule builds speed evenly and is only hampered by a computer-operated transmission that shifts like Dale Jarrett's grandmother. It is programmed to short-shift for maximum fuel savings and only becomes enjoyable under the control of the gear selector's manual-mode up-and-down buttons. An electric motor accomplishes the steering assist with the penalty of some numbness, and the brakes in the mule are hydraulic calipers in front and stock Contour drums in the rear with regenerative assistance from the motor. When the clutch disengages during downshifts, the regenerative feature shuts off, resulting in a jerky deceleration. The more sophisticated brake-by-wire system in the Prodigy concept should solve the problem by phasing in hydraulic pressure during shifts to provide a consistent brake feel.

A Ford hybrid you can buy will be the gasoline-electric version of the Escape sport-utility that is due in 2003 using the powertrain control strategy from the Prodigy and other selected ingredients. Expect to see improved batteries, an electric motor 50 percent more compact, and--dare we say it--better styling.

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Edited by empowah
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GM Precept

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And speaking of styling, the General appears to have been off its collective medication when it penned the Precept. It is different from its two counterparts in virtually every aspect and looks like Han Solo's toaster.

GM wanted to reach the PNGV goal of an 80-mpg family sedan, and the Precept does so in every measure except cost and cargo space. Where there should be a trunk is an Isuzu 1.3-liter, three-cylinder direct-injection turbo-diesel engine, moved aft so the nose and the undertray could be sealed up to make possible the astonishing 0.16 drag coefficient. That's better than the 0.19 generated by the best production car to date, the GM EV1. Airflow through the rear radiator array actually reduces drag by exiting out the back to partly fill in the drag-inducing low-pressure zone directly behind the car. The engine mates to a 13-hp "multipurpose unit," an electric wondermotor that starts the engine, drives the air conditioner, balances the crankshaft and gearbox input-shaft speeds so no transmission synchros are needed, generates power for the nickel-metal hydride batteries, and assists the engine during full-throttle acceleration. Where there should be an engine, there is another liquid-cooled 34-peak-hp electric motor from an EV1 driving the front axle independently. The Precept is the only design of the trio with two electric motors. It is also the only car with four distinct coolant circuits (engine, electric motors, batteries, and turbo intercooler), three separate voltage systems (12, 24, and 36), and 16 radiators. Only people strong in the ways of the Force are allowed under the rear hatch. A total of 47 microprocessors must report for work to make the Precept roll down the road.

Like the Toyota Prius, the Precept can run as a pure electric, its front-drive motor powering the car in reverse and away from stops. Once the car is in motion, the smaller, multipurpose motor starts the engine, which takes over for steady-state cruising. Under hard acceleration, both electric motors pitch in. The multipurpose motor is always busy charging the batteries, joining the larger front motor in regenerative braking, or driving the air-conditioning compressor when the engine is off. Although it is the most complicated, the Precept's powertrain is the most seamless of the three PNGV prototypes. With the exception of the engine start, a change in modes is nearly impossible to detect. Simply put the car in drive, and it goes, from 0 to 60 mph in 12.2 seconds, according to GM.

The fish-net-like mesh front seats are comfortable, even though the press kit makes the odd boast that they have "the bare minimum of foam padding and trim materials for the bolsters." It doesn't mention that rear-seat passengers are treated to the dubious thrill of staring at your rumpled shirt while you drive. To keep aerodynamic drag down on the aluminum-and-carbon-fiber body, side-mirror duties are accomplished with rear-facing cameras that display the view aft on cockpit LCD screens, which, on our day of testing, worked intermittently and disappeared in direct sunlight. By comparison, the images in the ESX3's prismatic mirrors were fuzzy around the edges but always reliable. But then, the Precept is a Hail Mary bomb, a touchdown at the 80-mpg goal, while the others are barely over the 50-yard line because of worries over cost and practicality.

Although GM is planning to build a full-size pickup with a hybrid powertrain that could be shared among vehicles, the Precept is too wonky and makes too many sacrifices for its 79.6-mpg combined rating and will likely never see production. In fact, it looks doubtful that we'll see an 80-mpg supercar in 2004 priced at less than an F-16 if the Precept is any indication of what it takes. Sure, the next 36 months is plenty of time to produce a few leaps in technology, but the government will have to raise your share of the bill.

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You will note that of these three automakers, only...well, actually none of these automakers has fully developed any of these concepts yet.

Leave it to Honda to perfect the fuel cell vehicle - how did GM manage not to get something close to the Precept up and running by now?

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the unitized body shell to come together from just 12 plastic moldings like a SnapTite model of the Charlie's Angels van.

I can already hear C&D whining about the panel gaps.

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I always did like the styling of the ESX3.

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Boy...they couldn't make the Precept any uglier could they? :yuck:

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You will note that of these three automakers, only...well, actually none of these automakers has fully developed any of these concepts yet.

Leave it to Honda to perfect the fuel cell vehicle - how did GM manage not to get something close to the Precept up and running by now?

:rolleyes:

Honestly, do you know if Honda's fuel cell setup is any better or worse than GM's that is in the Equinox fleet? Honda keeps getting this "wow, you've done it!" simply because of how they've set up their test program. They may be further along, but franky, it's hard to tell at this point. Until a manufacturer is confident enough to sell (not just lease) a fuel cell car, I don't think we can really say anyone has "perfected" a fuel cell system.

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:rolleyes:

Honestly, do you know if Honda's fuel cell setup is any better or worse than GM's that is in the Equinox fleet? Honda keeps getting this "wow, you've done it!" simply because of how they've set up their test program. They may be further along, but franky, it's hard to tell at this point. Until a manufacturer is confident enough to sell (not just lease) a fuel cell car, I don't think we can really say anyone has "perfected" a fuel cell system.

In terms of limited production vehicles thw FCX is further along I believe because it uses Gen V Cells whereas the Equinox uses Gen IV Cells, thus giving better packaging efficiency and longer ranger. Both a huge advancements though.

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who is doing the classification of fuel cells to label them "gen V or gen IV"? Is this something established outside the companies, or is it like Toyota saying the Prius is on its 3rd or 4th gen platform, so it must be better than anything else? Honest question.

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:rolleyes:

Honestly, do you know if Honda's fuel cell setup is any better or worse than GM's that is in the Equinox fleet? Honda keeps getting this "wow, you've done it!" simply because of how they've set up their test program. They may be further along, but franky, it's hard to tell at this point. Until a manufacturer is confident enough to sell (not just lease) a fuel cell car, I don't think we can really say anyone has "perfected" a fuel cell system.

You're right, I had forgotten this was still a lease program. GM seems to be more tentative at this point, but then they've got more to lose as well.

The auto mags should have their hands on the Clarity soon, I suspect. We'll know more then.

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who is doing the classification of fuel cells to label them "gen V or gen IV"? Is this something established outside the companies, or is it like Toyota saying the Prius is on its 3rd or 4th gen platform, so it must be better than anything else? Honest question.

I'm pretty confident that's marketing more than anything. I don't think there's anything like an ISO or SAE standard, if that's what you mean.

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Wow..I don't remember the Precept. Very Citroen-eque styling.

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who is doing the classification of fuel cells to label them "gen V or gen IV"? Is this something established outside the companies, or is it like Toyota saying the Prius is on its 3rd or 4th gen platform, so it must be better than anything else? Honest question.

I don't know who created the classification, but GM's has at least talked about a Gen V system, I just don't know if they've implemented it in any concepts yet.

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