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Blast from the Past

Chrysler’s return to rear-drive mid-size cars puts a Teutonic twist to an America classic.

Chrysler designers were inspired by the Chrysler 300s of the past.
By now you’ve probably read plenty of stories about rearwheel drive Chryslers and how the company spent all those years telling the auto-buying public that front drive was safer than rear drive. What’s the deal? Were they lying to us?

Those of us on this side of the business know that at the time front-drive was an inexpensive alternative that saved a car company on the brink of disaster spawning a front-drive revolution.

The long answer would be that the reardrive was chosen because that architecture offers the best vehicle balance and handling without compromising luxury. Look around. There aren’t any front-drive BMWs or Mercedes. But Chief Engineer Burke Brown has the one-word answer — Hemi.

“We couldn’t do a front drive car with a 340 hp Hemi,” he says.

The Hemi is certainly one of the best known brand names in the auto industry and DaimlerChrysler is leveraging that brand recognition. The powerplant, that made its debut in full-size pickups, has found its way into the Durango SUV and now into the 300C sedan and Magnum sport wagon.

 The top-of-the-line 300 interior features tortoise-shell accents.
The optional 5.7L Hemi delivers 340 hp at 5,000 rpm and 390 lb. ft. of torque at 4,000 rpm. The engine features a deep-skirt cast-iron block and aluminum heads. Burke Brown says that it has all of the ingredients that make a Hemi a Hemi — a double rocker shaft, dome pistons and a camshaft that sits high in the block.

Brown says that the architecture facilitated the development of the Multiple-Displacement System (MDS). The electronically-controlled system works similar to GM’s Displacement on Demand, using oil pressure to disable four cylinders under certain conditions.

Unlike GM’s system, which uses an add-on oiling plenum to fill the lifters, the Hemi’s hydraulic lifters are fed through oil passages machined into the block. With the use of Electronic Throttle Control and sophisticated algorithms the transition from four to eight cylinders can be done in 40 ms.

Brown says that it’s a simple design that runs seamlessly and results in a 10 to 20 percent savings in fuel economy.

“It allows us to have an engine with 340 hp and 390 lb. ft. of torque and still get the fuel economy of the larger 4.0L V-6 or small V-8,” he adds.

The Hemi is bolted to a 5-speed automatic transmission jointly developed by Chrysler and Mercedes, built at the Indiana Transmission Plant II in Kokomo, Ind. The transmission uses a ratio spread selected to minimize fuel consumption and reduce powertrain noise.

Front suspension is designed in the ‘philosophy’ of the Mercedes E-Class.
Bearings are used in place of bushings in several locations to reduce friction and a scavaging system removes oil spun off from rotating parts, saving energy that would be consumed by internal parts rotating in oil.

The fully adaptive electronic control system monitors transmission shifts adjusting hydraulic pressure as necessary. The system monitors accelerator pedal usage, brake usage and lateral acceleration adapting the shift schedule to individual driving styles.

Those not opting for Hemi power can chose from the base model’s 2.7L 190 hpV-6 or an optional 250 hp 3.5L V-6, both mated to a 4- speed automatic.

Chrysler calls the 300C ‘The return of the Great American Car’ albeit with a good dose of Teutonic DNA. Chrysler claims that the 300C and Magnum share Mercedes ‘philosophy’ but no actual parts.

During the first phase of the vehicle program Chrysler engineers are involved in technology sharing sessions with their Mitsubishi and Mercedes counterparts. Utilizing ‘tried-andtrue’ suspension chassis and electronic architectures cuts down on development time and cost.

Chrysler was then on it’s own until the program nears its end, when another technology sharing session takes place. These technical sessions often drive technology back the other way. The two-piece collapsible prop-shaft developed for the 300 platform will find its way into future Mercedes and Mitsubishi programs.
Chrysler engineers did raid the global parts bin for a few things. For example, the 300C uses the same Mercedes steering column found on the C-Class and Chrysler Crossfire. The greatest amount of sharing involves electronic architecture. The 300 utilizes the global CAN BUS system and other electronic systems. The design of the new car is quite a departure from the cab-forward 300M and Concorde that it replaces. Chrysler refers to the design of the 300 as ‘uniquely American styling’, drawing cues from the great Hemipowered sedans of the past.

Senior Product Designer John Opfer says that the design team was involved in the initial packaging phase of the program along with manufacturing engineers — all becoming part of the creative process.

The front seat’s H-point is 2.5 in. higher than Concorde. Chrysler felt that the 300 may bring people out of SUVs who demand a more prominent seating position. A higher H-point also allows for more leg room as the engine compartment encroaches into the cabin and the higher seating position works better with the vehicle’s high belt line.

The gauges are styled after the Smith Yeager gauges found on the Chrysler 300’s of the ’50s. The interiors feature real wood trim, a dashmounted analog clock and the first real-world use of tortoise-shell accents, available on the top line model. A 60/40 folding slit rear seat is accessible from the trunk.

Designers pushed the wheels out to the corners to add to the vehicle’s stability. The 300 sits on a 112 in. wheelbase, four in. longer than a Pacifica and eight in. longer than an E-Class. The 63-in. track is 3 in. shy of the Pacifica and 1 in. wider than the E-Class. Weight distribution is 53/47 front to rear.

The front suspension is based on the EClass four-link system. The high upper control arms place the upper ball joints above the tires helping to keep the tires perpendicular to the road during cornering.

In place of a one-piece lower control arm, lateral links and tension struts attach to the steering knuckle via separate ball joints. Chrysler says that multiple bushings offer more flexibility to tune for ride and handling. The aluminum five-link independent rear suspension is mounted to a steel cradle attached to the body with four large rubber mounts, isolating all suspension components except the coil springs and shocks which use premium joust bumpers to minimize harshness.

Four-wheel discs use 12.6 by 1.1 in. vented front rotors and 12.6 by .4 in. solid rears. The Hemi C boasts vented discs on all four corners, bumping the front rotors to 13.6 in. Both 300C and Magnum will get the optional Mercedes 4Matic four-wheel-drive system this summer. The Steyr-supplied system uses a front differential with a 62-38 frontto- rear torque split.

Supplier involvement

Airbags – driver and passengerTakata
Airbags – side curtain TRW
Brakes Bosch
Console Collins & Aikman
Cooling Module Valeo
Exhaust system Eberspaecher NA
Half shaftsDelphi Saginaw Steering
Headlamps Valeo
IP assemblyCollins & Aikman
Exterior mirrorsSchefenacker
Seats/Overhead system JCI
Shock absorber ZFSachs
SunroofInalfa Roof Systems
Suspension moduleBenteler
Wiper module Denso
Chrysler engineers are the first to admit that bringing a rear-drive car to market wouldn’t be possible without modern electronic-controlled ABS and traction control systems.

The 300 platform uses the global DaimlerChrysler ESP (Electronic Stability Program), supplied by Continental-Teves. The system utilizes a steering sensor, a yaw sensor, a four channel brake system with a TRW brake booster and electronic throttle control to stabilize the vehicle in wet and slippery conditions. The software has been programmed specifically for each different engine and tire combination.

The 300C/Magnum platform was designed to perform well in the event of an accident.

The octagonal-shaped forward frame rails are made of dual-phase steel allowing for very good axial crush. The engine cradle has also been designed to crush along with the frame rails.
In the event of a frontal impact, a toeboard crossmember sheds the load both across the car and out into the sills to reduce the amount of deformation in the passenger compartment. In a high-speed offset crash, the wheel engages in a tire catcher structure built into the back of the front wheel well and transfers load into the sill reducing the amount of deformation in the safety cage.

The body also features nesting fan motors and a two-piece collapsible prop shaft.

Single stamped outer and inner side panels with multi-piece reinforcements and hefty seat cross members add to the body’s stiffness. The Magnum and 300C already meet the requirements of NHTSA’s 50 mph rear crash test, two-and-a-half years ahead of the deadline. The rear rail structure is designed to channel load forward and down into the sill. The spare tire is mounted at an angle and folds up with the rear.

The 300C/Magnum is the fourth new product from DaimlerChrysler to meet the Government requirements for the advanced airbag ruling.

The 300 is among the first Chrysler group vehicles to offer multi-stage airbags for both driver and passenger. The passenger seat uses a weight-strain system for occupant-sensing. Available side curtain airbags extend all the way to the rear of the back seat. Magnum and 300 use a direct tire pressure monitoring system that monitors pressure inside each tire.

The 300 will be available in four trim levels, the standard 300, 300 touring which replaces the 2.7L V-6 with a 3.5L V-6, the 300 limited and the 300C with the Hemi. MSRPs range from $23,595 for the base car to $32,995 for the 300C.

Optional features include ultrasonic rear object detection, self-sealing Continental tires, UConnect, power adjustable pedals, a 380-watt Boston Acoustics digital sound system, GPS navigation radio with integrated six-disc CD/MP3 player, SIRIUS satellite radio and Xenon headlamps with high-pressure washers.

The Name Game

Finally, a public clinic with positive results.

Senior Product Designer John Opfer says that when it comes time to attach a name to a new vehicle, everyone gets involved. Mike Perugi, brand manager, Chrysler marketing, premium vehicles confesses that the new 300 was actually named by the target audience.

Chrysler initially cliniqued the car as the Nassau and even went as far as developing badging for the vehicle. But Perugi says that as soon as the prospective buyer took one look at the car they said, “That’s the new Chrysler 300.” The name stuck.

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