It was used for the entry-level XJ6 in Britain and Europe but rarely, if ever, seen in models exported to the US. The SOHC 2.9, which was generally considered somewhat underpowered for such a large car, was discontinued in 1990 (Actually 3.2 starts with a J-plate, so late 90 2.9 is possible) and replaced with a DOHC 3.2 (essentially identical to the DOHC 4.0). The 2.9 Engine was, as in earlier years the 2.8 XK-engine, sized to match road-tax regulations in some European Countries like Italy or France. In France cars with more than 3 litres of engine size had to pay a luxury tax. Unlike all other AJ6's, the 2.9l used Bosch LH Jetronic fuel injection and EZ-K ignition (rather than Lucas 9 or 15CU EMS) 4.0 (1989–1994) The 24-valve DOHC version replaced the AJ6 in 1989. It featured a longer stroke, and generated power at 4,750 rpm and of torque at 3,650 rpm. The engines as used in the 1990–1994 XJ40 cars continued with the crank sensor and empty distributor type of ignition system and the hot-wire Mass Air Flow sensor type of fuel injection control system as the 1988–1989 XJ40 cars. TWR modified XJ40s resulting in the XJR. Jaguarsport was also formed as a partnership between TWR and Jaguar. The first XJR, the XJR , had extensive appearance changes coupled with stiffer suspension, anti-roll bar/links, power steering valve that reduced efficiency by 40% and an LSD but no performance enhancements. Interior-wise it included special stitching, "sport" or "XJR" embossed front headrests, and Jaguarsport speedometer labels and tread-plates. 1990 XJRs had the upgraded 4L engine with the old style body-kits, and appearance changers. XJR 4.0Ls from 1990 on had all of the XJR 3.6 handling upgrades and benefits from engine enhancements such as high lift cams, improved double plenum inlet manifold, and a compression ratio of 9.75:1. They were sent to TWR in Coventry to be modified directly after being produced. The exterior changed again for the last generation of the XJ40 XJR (from H-registration year onwards). Bodykit was re-sculptured and the boot spoiler was deleted. Side mouldings were added, with the smaller "XJR" badge embedded in them. Engine had a plaque saying "Jaguarsport XJR 4L" on the rocker cover. XJR badge size was decreased on the boot (had previously ranged from XJR-3.6, XJR-4L, 4-litre and "XJR". The later one ("XJR") is most common and the only badge