The Jaguar AJ-8 is a compact DOHC V8 piston engine used in many Jaguar vehicles. It was the fourth new engine type in the history of the company. In 1997 it replaced both designs previously available on Jaguar cars: the straight-6 Jaguar AJ6 engine (or rather its AJ16 variant), and the Jaguar V12 engine. It remained the only engine type available on Jaguar until 1999 with the launch of the S-Type, when the Jaguar AJ-V6 engine was added to the list. The AJ-V8 is available in displacements ranging from 3.2 L to 5.0 L, and a supercharged version is also produced. Ford Motor Company used this small V8 in other products as well, including the Lincoln LS the 2002-2005 Ford Thunderbird as well as in several Land Rovers and the Aston Martin V8 Vantage.
The AJ-V8 was designed to use Nikasil-coated cylinders rather than the more-common iron cylinder liners. However, like the BMW M60, high-sulphur fuel reacted with the Nikasil liners and caused engine failures. Jaguar replaced affected engines, and has used conventional cast-iron linings ever since.
The engine originally used a two-state Variable Valve Timing system to switch the intake cam timing by 30°. Newer variants use a more sophisticated system which can vary intake timing incrementally up to 48°. The Lincoln version was made in the United States.
Other engine features include fracture-split forged powder metal connecting rods, a special one-piece cast camshaft, and reinforced plastic intake manifold.
The AJ-V8 was on the Ward's 10 Best Engines list for 2000. The 4.0 L (3996 cc) AJ26 engine was introduced in 1996. The number "26" comes from 12+6+8 (cylinders), because when the first ideas were sketched, a family of 6-, 8- and 12-cylinder engines was contemplated, although only the 8-cylinder version was produced. It has a square 86 mm (3.4 in) bore and stroke. It was updated in 1998 as the AJ27 with continuously variable valve timing. The AJ-V8 was updated again in 2000 as the AJ28. The naturally aspirated version produces 290 hp (216 kW) in the 2000-2002 XK8.[WIKI]
|