X-BODY CARS -- ENGINEERING THE PACKAGE

General Motors' so-called "X-body" cars are available in the Corporation's Chevrolet (Citation), Pontiac (Phoenix), Buick (Skylark) and Oldsmobile (Omega) lines. They are front-wheel drive cars with transverse engines and rack-and-pinion steering mounted to a unitized body. The power train (engine, transmission, universals and drive shafts), steering and front suspension are bolted to a cradle; the entire assembly is attached to the body using rubber noise and vibration isolators. This arrangement eases maintenance. The front suspension has MacPherson struts with coil springs and a stabilizer bar. The rear suspension has been called a trailing arm twist axle. An upside down, U-shaped HSLA (High Strength Low Alloy) axle is located by an HSLA control arm at either end and by a Panhard rod (or track bar). Inside the U-shaped axle is a sway bar that varies in thickness according to the suspension package ordered. The front bar also varies with the suspension packages as do both front and rear spring rates, bushing rates and shock valving. The track bar orientation and control arm angle were designed to minimize lateral pull and maintain understeer at all passenger loads and place the roll axis to simulate the roll feel of a large car. The track bar section was designed with large twist angles to provide a soft ride. A feature probably unique to this car is the use of the rear jounce bumpers as secondary springs. They are hollow, articulated urethane bumpers mounted on the top of the shock absorbers to help achieve a variable rate suspension. Engines available are a 60 degree -V 6-cylinder, and an in-line 4-cylinder. Both manual (4-speed) and automatic transmission are available. Brakes are disk in front, drum in rear. Fuel economy for the models as a whole will average 25 mpg and certain drivetrain combinations will be capable of delivering 40 mpg.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/31209162
• Corporate Authors:

  Automotive Industries International

  Chilton Way
  Radnor, PA  United States  19089
• Authors:
  • MCELROY, J
• Publication Date: 1979-4

Media Info

• Pagination: p. 36-43
• Serial:
  • Automotive Industries
  • Volume: 159
  • Issue Number: 4
  • Publisher: Randall Publishing Company
  • ISSN: 1099-4130
  • Serial URL: http://www.ai-online.com

Subject/Index Terms

• TRT Terms: Automobiles; Automotive engineering; Bumpers; Disc brakes; Engines; Front wheel drive; Low alloy steel; Vehicle power plants
• Old TRIS Terms: Automobile engines; Transversely mounted engines; V-six engines
• Subject Areas: Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 00314826
• Record Type: Publication
• Source Agency: Engineering Index
• Files: TRIS
• Created Date: Oct 27 1980 12:00AM