than a third of Italian sales in the Prisma's class were of diesel-powered cars. Its naturally aspirated 1929 cc SOHC four-cylinder had an iron block, aluminium head and indirect injection; it put out 65 PS. The engine had been developed by Fiat, and was also installed in the Fiat Regata DS—although the Fiat lacked some of Lancia's NVH-improving solutions. The diesel engine was light, only weighing more than the 1.6-liter petrol unit. All Diesel Prismas sported a sightly domed hood, needed to clear the taller engine. Some updates were introduced with the diesel, including optional hydraulic power steering, redesigned seats, new striped cloth upholstery and a four-spoke steering wheel. About a year later, in May 1985, the Prisma turbo diesel was added to the range. The 1.9-litre engine from the Prisma diesel received a KKK turbocharger with wastegate valve, an intercooler and an oil cooler; its gearbox was the same ZF 5-speed unit used on the Delta HF turbo. Power was 80 PS and torque . The turbo diesel Prisma adopted disk brakes, wheels and tyres from the top-of-the-range 1600 as well as similarly rich equipment, and added standard power steering. 1986–1989, second series A major mid-cycle refresh débuted at the April 1986 Turin Motor Show. Changes were made to the exterior and interior of the car. Outside there were more modern, enveloping bumpers—the front one with provisions for integrated fog lights; the redesigned grille and bonnet bore a family resemblance to the flagship Thema. Also new were the ventilation grille on the C-pillar and full-wheel hubcaps. Inside new seats, new instrumentation and air conditioning system. The 1986 range included seven models, two of them all-new: 1.3, 1.5, 1.5 Automatica, 1.6, 1.6 i.e., 4WD, diesel and turbo ds. 1.3 and 1.5 models had revised intake and exhaust system, fuel cut-off, a new carburettor and breakerless ignition. The diesel versions had also received some minor engine updates, and the turbo diesel had been renamed turbo ds. The new Prisma 1.6 i.e. used a version of the 1585 cc twin-cam engine equipped with Weber-Marelli IAW integrated electronic ignition and fuel injection system, developing 108 PS. In comparison to the carburetted Prisma 1600—which remained on sale as Prisma 1.6—further changes had been made: the cylinder head had been rotated 180°, bringing the exhaust side to the front for better cooling, and the whole engine was canted forward 18° to lower its centre of