The Isuzu Piazza is a small, sporty 3-door liftback coupé which was manufactured by Isuzu from 1981 until 1992 in two generations. The Isuzu Piazza was marketed as the Isuzu Impulse in North America and as the Holden Piazza in Australia.
The first generation Piazza was a rear-wheel drive car, and in the United Kingdom it was the first widely available Isuzu passenger car. The second generation was available as front-wheel drive or all-wheel drive. It was the basis for the lower-priced Gemini Coupé, known as the Geo Storm in the US market.
First generation (JR120/130; 1980)
Rear view of a Piazza Nero XJ (Japan)
For the US market, this vehicle was introduced as the Impulse in 1983. For the 1983 and 1984 model years, only one engine was available, the 2.0 L SOHC inline-four engine, rated at 90 hp (67 kW), 108 lb⋅ft (146 N⋅m). A MPFI turbocharged model was introduced in 1985, with a 2.0 L SOHC engine rated at 140 hp (104 kW) and 166 lb⋅ft (225 N⋅m). The 1987 model year had the RS model which came with a 4ZC1 turbo engine. The 1988 model year saw several changes. Mild exterior and interior changes were made to the appearance of the vehicle (including a larger rear spoiler and fixed headlights without pop up covers).
In the US market, the Impulse was marketed as «everything standard», meaning that all Impulses came with all available equipment for the vehicle’s model year, and only two trim levels offered: non-turbo and Turbo. There were, however, some special edition models, most notably the RS model of the 1987 model year, available only in white body color with pewter color trim, and featuring the stiffest suspension available on any Impulse, very close to the Irmscher suspension sold only in Japan. For the 1989 model year, a Special Edition non-turbo model was offered which was equipped with the Turbo model wheels and interior trim.
The vehicle was sold as the Piazza in Europe and Australia, though introduced into these markets in 1985 or later.
In the UK the Piazza was sold in only one trim level and only Turbo form, with a 147 bhp 2.0 Turbocharged engine (4ZC1-T).
The Piazza had a shaky start in the UK with the first importer Isuzu GB, based in Maidstone, Kent going out of business in 1986, and London car dealer Alan Day bought the remaining stock of Piazzas at a bargain price. These cars were sold by Alan Day at significantly reduced price; the main reason Isuzu GB went out of business was due to high unit price. In 1987 International Motors Group of West Bromwich (IM Group) were awarded the official Isuzu franchise for the UK. (They also at the time represented Subaru and Hyundai in the UK.) IM Group still marketed the Piazza in single trim/engine form, but they only sold the updated ‘Lotus’ Piazza. The earlier cars sold by Day became known as ‘pre-Lotus’ cars; the suspension and handling of these pre-Lotus cars was derided by UK Press as poor, especially the live axle arrangement at the rear, which by the late ’80s was seen to be antiquated. The updated ‘Handling by Lotus’ car was available from 1987 and the handling, although keeping the live axle arrangement, was transformed by Lotus in the UK after significant development work, involving modified suspension layouts, larger brakes, specially produced dampers and Goodyear tyres. The ‘Handling by Lotus’ cars had updated interior and exterior equipment. The exterior having a redesigned rear, with a large ‘hoop’ spoiler, new rear lamps, new rear badging with ‘Handling by Lotus’ badges and removal of the rubber side bumper strakes for a cleaner, more modern look. The updated interior trim was mainly ‘tweed’ check fabric, an updated centre console, but the loss of air conditioning to keep the price down for the UK market.
The Piazza was marketed in Australia as the YB series Holden Piazza
Isuzu (UK) Ltd, the West Bromwich-based importer, sold the Lotus Piazza from 1987 to 1989, before concentrating on the 4WD Isuzu Trooper. They never sold the second generation Piazza in the UK, nor was it sold in any European market.
In the US, the Impulse was replaced by the second generation Impulse after the end of the 1989 model year. However, in Japan, the first generation Piazza continued production and was available through the 1991 model year.
Second generation (JT22; 1990)
Isuzu Impulse RS Turbo, rear view
The three-door hatchback debuted as the Impulse XS in 1989 for the 1990 model year. It was offered only in front-wheel drive with a DOHC 1.6 L (1588 cc) I4 engine which produced 130 hp (97 kW) and 102 lb·ft (138 Nm). The suspension consisted of MacPherson struts both front and rear, with a rigid trailing arm front suspension and a multi-link rear suspension, featuring Nishiboric passive steering.
For the 1991 model year, the Impulse RS was introduced with a 160 hp (119 kW) and 150 lb·ft (203 Nm) turbocharged engine and all-wheel drive drivetrain which featured rear viscous differential and center planetary differential and viscous coupling. The wagonback model was also introduced for the 1991 model year, only available with the normally aspirated 1.6 L engine.
1991 Isuzu Impulse RS interior showcasing the «space capsule» design theme
A non-Lotus innovation in the Impulse was the development of the Nishiboric passive rear-wheel steering system which adjusted the toe of the rear wheels by changing the rear wheel alignment through the range of suspension travel.
The combination of the burst of the Japanese economic bubble, rising emissions and crash safety requirements, and continued restrictive market segment changes by General Motors forced Isuzu out of the car making market and brought an end to the Impulse.
1993 Asüna Sunfire
In the Japanese market, this vehicle was sold as the Piazza from July 1991 through the spring of 1992. The second generation Piazza was offered only in front-wheel drive with the 1.8 L engine. All of the second generation Piazzas came with the Lotus-tuned suspension. The Japanese were also offered the Geo Storm version of the Piazza, called the Piazza PA-Nero. This model was exclusive to the Japanese import dealership network Yanase Co., Ltd., under a special arrangement that sold GM products in Japan.
- «Impulse JR Specifications». Retrieved 2007.
- Holden Piazza sales brochure, General Motors-Holden’s Sales Pty Ltd, March 1986
- «Impulse JI and Asuna Sunfire Specifications». Retrieved 2007.