Jaguar AJ-V8 engine

The Jaguar AJ-V8 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. It was an in house design with work beginning before Ford's purchase 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 3.2L to 5.0L, and a supercharged version is also produced. Ford Motor Company also used this engine in other cars, including the Lincoln LS and 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 coating 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.
Ford ceased production of the AJ-V8 engine in September 2020 when it closed the Bridgend Plant. However, in August 2020 JLR was able to take over production means for the AJ-V8.
The AJ8 engine was manufactured in a dedicated Jaguar facility located within the Ford Bridgend Engine Plant in Bridgend, South Wales. The Jaguar "plant-within-a-plant" saved considerable investment costs by Jaguar. It was staffed by workers dedicated to Jaguar engine production and included a linked flow-line of computer numerically controlled machines with automated loading and assembly. Component supply was on a "just-in-time" basis.
Jaguar Land Rover has subsequently produced the AJ supercharged petrol V8 Jaguar Land Rover engines in a state-of-the-art Engine Manufacturing Centre in Wolverhampton.
The 4.0 L (3,996 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 (3.39 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; 294 PS) in the 2000–2002 XK8.
Vehicles using this engine:
The supercharged version of the AJ26 is used in the high-performance R versions of Jaguar's cars. The engine was updated with AJ27 specifications for 2000. It produces 370 hp (276 kW; 375 PS) and 387 lb⋅ft (525 N⋅m) with the help of an Eaton supercharger (modified Roots-blower). The supercharged engine did not use variable cam timing as the normal benefits of improved volumetric efficiency are not noticeable on a boosted engine.
Vehicles using the supercharged version include:
The 3.2 litre variant was the second to be introduced. It reduces the stroke to 70 mm (2.76 in) and power falls to 240 hp (179 kW; 243 PS) and 233 lb⋅ft (316 N⋅m). This variant was not available in the North American market.
Vehicles using this engine:
The 3.6 L; 216.9 cu in (3,555 cc) engine, marketed as a "3.5", was only used in the XJ series. The stroke was 76.5 mm (3.01 in). Output was 262 bhp (195 kW; 266 PS) at 6,250 rpm and 345 N⋅m (254 lb⋅ft) at 4,200 rpm.
Vehicles using this engine:
The 3.9 L (3,934 cc) AJ30/AJ35 variant is a unique displacement used only by Ford and Lincoln and is built in Ford's Lima, OH engine plant. Bore and stroke is 86 mm × 85 mm (3.39 in × 3.35 in). The AJ35 version introduced for the 2003 model year added variable valve timing of the intake camshafts and electronic throttle control. While the block, crankshaft, pistons, and connecting rods are all unique to this displacement, many other parts are shared with the AJ-V8 engines produced in the UK by Jaguar.
Vehicles using this engine:
The last AJ35 was produced in March 2006 after only 3 years. Total run of AJ30/35 was nearly 250,000 units
The 4.196 L; 256.1 cu in (4,196 cc), AJ33 and AJ34 versions retain the 86 mm (3.39 in) bore with 90.3 mm (3.56 in) stroke. It was introduced in 2002 as the AJ33 and produces 294 hp (219 kW; 298 PS) at 6,000 rpm with 303 lb⋅ft (411 N⋅m) of torque at 4,100 rpm, later increased to 300 hp (224 kW; 304 PS) and 310 lb⋅ft (420 N⋅m).
Vehicles using this engine:
The AJ33S is a supercharged/intercooled variant of the AJ33. It was introduced in 2002 to replace the 4.0 SC and produces 390 hp (291 kW; 395 PS) at 6,100 rpm with 399 lb⋅ft (541 N⋅m) of torque at 3,500 rpm. The engine was later updated to AJ34S specification to include Variable Valve Timing as well as other minor updates.
Vehicles using this engine:
Land Rover also offered a supercharged version of the 4.2 L as that company's high-performance engine. Land Rover's version is not the same as the Jaguar's version but it was adapted from it.
Applications:
The 4.4 L; 268.1 cu in (4,394 cc) AJ41 version features an 88 mm × 90.3 mm (3.46 in × 3.56 in) bore and stroke. This engine replaced the BMW M62 engine used in 2003-2005 Range Rover models.
Applications:
Aston Martin hand-assembles a special version of the AJ-V8 for the 2005 V8 Vantage known as AM05 – or while it was under development as AJ37. This unit displaced 4.3 L; 261.2 cu in (4,280 cc) and produces 380 bhp (283 kW; 385 PS) at 7,000 rpm and 409 N⋅m (302 lb⋅ft) at 5,000 rpm. This engine is unique to Aston Martin and features race-style dry-sump lubrication, which enables it to be mounted low to lower the centre of gravity. The firing order is the same as the other AJ-V8 engines although the cylinder numbering is different (AJ37 = 1-5-4-2-6-3-7-8 vs. AJ26 = 1-2-7-3-4-5-6-8). The engine is assembled by hand at the AM facility in Cologne, Germany, which also builds the V12 for the DB9 and Vanquish. The cylinder block, cylinder heads, crankshaft, connecting rods, pistons, camshafts, inlet and exhaust manifolds, lubrication system and engine management are all unique to the Aston Martin version.
In May 2008, Aston Martin released a new design that used pressed cylinder liners instead of cast-in liners. This allowed for thinner liners, and a higher capacity of 4.7 L (4,735 cc; 288.9 cu in) for the V8 Vantage. Called the AM14, power output increased to 420 bhp (313 kW; 426 PS) (an 11% increase on the previous 4.3-litre unit) and peak torque to 470 N⋅m (347 lb⋅ft) (a 15% increase). The Aston Martin V8 Vantage S features the same 4.7-litre V8 engine found in the base Vantage, but with improved intake airflow, new mufflers, and new programming that keeps the exhaust system's bypass valves open longer. The engine in the V8 Vantage S now develops 430 bhp (321 kW; 436 PS) at 7,300 rpm and torque of 490 N⋅m (361 lb⋅ft) at 5,000 rpm representing an increase of 10 bhp (7 kW; 10 PS) and 20 N⋅m (15 lb⋅ft) respectively. This engine is also used in the bespoke Aston Martin DB10 concept car for the 2015 James Bond film Spectre.
4.3, bore and stroke 89 mm × 86 mm (3.50 in × 3.39 in)
4.7, bore and stroke 91 mm × 91 mm (3.58 in × 3.58 in)
Applications:
An all new direct injection 5.0 L engine family was introduced in 2009, for the 2010 model year. The AJ133 is a 90° V8 engine available in either supercharged or naturally aspirated form, with a bore & stroke of 92.5 mm × 93 mm (3.64 in × 3.66 in) and a compression ratio of 9.5:1 for the supercharged version and 11.5:1 for the naturally aspirated one respectively.
The main structural components of the engine are all manufactured from aluminium alloy. The engine is built around a very stiff, lightweight, enclosed V, deep skirt cylinder block, with an open-deck design. A structural windage tray is bolted to the bottom of the cylinder block to further improve the block stiffness, minimize NVH (noise, vibration and harshness) and help reduce oil foaming. To further enhance the stiffness of the lower engine structure, a heavily ribbed sump body is installed. The sump body also helps to reduce engine noise.
A spheroidal graphite cast-iron crankshaft is utilized with high-strength cast pistons and fracture-split forged steel connecting rods manufactured from 36 Mn VS4 steel.
The engine uses a Bosch high pressure direct injection fuel system with fuel pressure provided by two, cam driven high pressure pumps which are driven by a dedicated camshaft. The high pressure pumps supply the fuel rails which in turn supply the four injectors for that bank with fuel at a controlled pressure.
The four camshafts incorporate VCT (variable camshaft timing). VCT allows the timing of the intake and exhaust valves to be adjusted independently of each other.
The naturally aspirated engine features cam profile switching and variable tract length inlet manifold.
Supercharged engines make use of a sixth-generation 1.9L TVS (Twin Vortices Series) supercharger, which is located in the 'vee' of the engine and is driven from the crankshaft by a dedicated secondary drive belt.
Denso's Generation 1.6 Engine Management System was used on earlier models, later switching to Bosch's MED17 engine management 2013+ (except for the XKR and XKR-S).
The direct fuel injection system, advanced piston and combustion chamber design and the supercharger provide improved fuel consumption and emissions, as these engines meet EU5 emission regulations in Europe and Rest of World (ROW) and ULEV 70 emission regulations in North American Specification (NAS) markets.
The naturally aspirated engine was replaced by the AJ126 supercharged V6 engine starting for the 2013 model year. It has since been replaced by the all-new Ingenium turbocharged inline-6 engine.
As of December 2024, Jaguar has discontinued most of its internal combustion engine (ICE) models, including those featuring the AJ133S, as part of its transition to an all-electric lineup by 2025. The 2024 Land Rover Defender V8 is the final vehicle to use the AJ133S engine. For the 2025.5 model year, it was joined in Defender by BMW’s 4.4L N63 twin-turbo V8 in the Octa derivative, (NC11 had already been introduced in the 2022 Range Rover and 2023 Range Rover Sport).
Land Rover version is called 'LR-V8 Petrol engine'.
The AJ133S is the supercharged variant of the AJ133, featuring an Eaton TVS1900R supercharger. It incorporates twin water-to-air intercoolers and a front-mount heat exchanger, with a shared cooling circuit. Differences over the naturally aspirated engine include; flat-top pistons for a lower compression ratio (9.5:1 vs 11.5:1), piston-oil spray jets, and different intake camshafts without cam-profile switching capabilities.
All AJ133S engines utilize the same supercharger pulley setup, capable of producing approximately 15PSI of boost. Differences in ECU calibrations determine the final power output.
Over its production span, the AJ133/S underwent several modifications to enhance performance, reliability, and compliance with evolving emission standards. Key changes by model year include: 2010:
2011:
2013 (excluding XKR & XKR-S):
2014:
2021 (specific to F-Pace SVR & F-Type P450/P575):
2024:
These updates aimed to address known issues and improve the engine’s overall performance and durability. For instance, the timing chain and tensioner revisions were implemented to enhance reliability. Additionally, the shift to Bosch engine management systems facilitated better integration with modern vehicle electronics and emission control systems.
The AJ126 V6 uses a AJ133 V8 engine block with the rear two cylinder bores blanked, and reduced bore sizes on the remaining six cylinders. While the engine block is the same size as the V8, the cylinder heads are shortened versions of the V8 heads. It is made on the same production line as the AJ133.
The AJ126 is a 3.0 L; 182.8 cu in (2,995 cc) 90° petrol V6, having a bore and stroke of 84.5 mm × 89 mm (3.33 in × 3.50 in) with a 10.5:1 compression ratio. It is supercharged and liquid cooled featuring direct fuel injection, four overhead camshafts and four valves per cylinder. There are two versions differing in power produced, a standard version making 340 PS (250 kW; 335 hp) at 6,500 rpm and 332 lb⋅ft (450 N⋅m) between 3,500-5,000 rpm and a high-performance variant making 380 PS (279 kW; 375 hp) at 6,500 rpm and 339 lb⋅ft (460 N⋅m) between 3,500-5,000 rpm. A special Jaguar F-Type 400 Sport model made 400 PS (294 kW; 395 hp) and 339 lb⋅ft (460 N⋅m).
The AJ126 engine is equipped with an Eaton TVS Roots-type supercharger. Specifically a 1.3L Eaton TVS R1320, mounted in the engine’s “vee” and is known for its compact design, efficiency, and ability to deliver smooth, immediate power.
Jaguar has since replaced the AJ-126 with an all new Ingenium turbocharged inline-6 engine.