North America[edit]
There is no one definition for an
SUV.[4] Most government regulations simply have categories for "off-highway vehicles," which in turn are lumped in with pickup trucks and minivans as "light trucks."[4] The auto industry has not settled on one definition.[4]
Nevertheless, four-wheel-drive
SUVs are considered light trucks in North America (and two-wheel-drive SUVs up to the
2011 model year[5]) where they were regulated less strictly than passenger cars under two laws in the
United States, the
Energy Policy and Conservation Act for fuel economy, and the
Clean Air Act for emissions.[6] Starting in 2004, the
United States Environmental Protection Agency (
EPA) began to hold sport utility vehicles to the same tailpipe emissions standards as cars.[7]
Many people question "how can an SUV be called a truck?"[8] Although the original definition of the "light truck" classification included pickups and delivery vans, usually SUVs and minivans are included in this category because these vehicles are designed to "permit greater cargo-carying capacity than passenger carrying volume.[8]
Manufacturing, emissions, and safety regulations in the
U.S. classify "an SUV is a truck"; however, for local licensing and traffic enforcement, "an SUV may be a truck or a car" because the classification of these vehicles varies from state to state.[9] For industry production statistics, SUVs are counted in the light truck product segment.[10]
http://en.wikipedia.org/wiki/Sport_utility_vehicle
The Audi S4 is the high performance variant of Audi's compact executive car A4. The original Audi S4, built from
1991 until
1994, was a performance-oriented version of Audi's
100 saloon/sedan. All subsequent S4s since
1997 have been based on the Audi A4; and as the A4 has evolved from one generation to the next, so has the S4.
A more powerful internal combustion engine, larger upgraded brakes, firmer suspension, larger roadwheels, and distinctive sheetmetal, styling clues and badging have always been amongst the many upgrades the S4 receives over its mainstream 100 and A4 siblings. In markets where the even higher-performance Audi
RS4 is not offered, the S4 is the top-of-the-line trim of the A4 family.[
1][2]
Like its regular A4 counterpart, all S4 variants have had longitudinally oriented, front-mounted engines. A single turbocharged
2.2 litre inline five-cylinder powered the original C4 version, and a 2.7 litre twin turbocharged V6 engine was found in the B5 generation. The B6 and B7 versions shared a common 4.2 litre V8 engine, the first time that a V8 engine was placed in a compact executive car, placing it in direct competition with the
BMW M3 which at the time had a 3.2 L inline 6. The recently introduced B8 generation uses a supercharged
3.0 litre V6
TFSI engine and competes with the
BMW 335i.[1]
All versions of the S4 have their transmission mounted immediately at the rear of the engine in a longitudinal orientation, in the form of a transaxle, and like all Audi "S" cars, are only available as standard with Audi's quattro four-wheel drive (
4WD) system, using a Torsen-based centre differential system.[3]
- published: 14 Apr 2016
- views: 5