Jaguar XF-R

When the Jaguar XF was first launched, it was available with 3 engines – a 3.0 litre V6, a 4.2 litre V8 and a supercharged 4.2 litre V8 (AJ34 and AJ34S). Then came the range-topping XFR, with an AJ-V8 Gen3 (AJ133) engine – 5.0 litres of displacement, 510 PS and 625Nm of torque.

Jaguar AJ-V8In certain or most markets, the non-R XF is also now offered with variants of the new AJ133 5.0 litre V8 engine. Depending on the market, it either complements or replaces the 4.2 litre previous generation AJ engine. A normally aspirated XF 5.0 makes about 385 PS while the supercharged version makes 470 PS, which is less power than the XFR’s 510 PS tune.

The new AJ133 5.0 litre V8 engine uses an all-new high pressure die-cast aluminium block with cast-in iron liners and cross-bolted main bearing caps. Despite the larger displacement, it is more compact – shorter by 24mm thanks to relocation of the oil pump. It has direct injection, which allows the compression ratio to be raised to 11.5:1 in the normally aspirated model, and from 9.0:1 in the 4.2 V8 supercharged up to 9.5:1 in the new 5.0 V8 supercharged.

The engine also features a new type of variable cam system. The four VCT (variable cam timing – intake and exhaust, 2 V banks) units move via positive and negative torques generated by opening and closing the intake and exhaust valves instead of by hydraulics. This allows the engine oil pump to be reduced in size and consumes less power. The supercharger and intercooler are packaged within the V-bank of the new engine – this reduces engine height and helps comply with pedestrian crash safety regulations.

The normally aspirated version features a variable inlet manifold and also camshaft profile switching on the intake cam, using hydraulically-operated two-piece tappets. The low-speed cam uses a 214 degree duration and 5.5mm valve lift while the high-cam uses a 250 degree duration and 10.5mm valve lift. The switch between low and high cams happens at 2,800rpm at high load, and this varies up to 4,500rpm at lighter loads.

UPDATE: Jaguar Malaysia (SISMA Auto) will be bringing in the 510 PS 5.0 litre supercharged Jaguar XFR into Malaysia this August. The product line-up will change somewhat. In Malaysia, the 3.0 V6 will remain, but the 4.2 normally aspirated will be replaced by the 5.0 normally aspirated, and the 4.2 supercharged will be replaced by the XFR. The non-R 5.0 supercharged in 470 PS tune will not be sold here, probably because it will be too close to the XFR.