Isuzu Piazza, Impulse, Storm Second Generation 1990–1991 And 1993 In Canada
| Second generation (JT22) | |
|---|---|
 |
|
| Overview | |
| Also called | Asüna Sunfire (Canada) Isuzu Impulse (North America) |
| Production | 1990–1993 |
| Body and chassis | |
| Layout | Front engine, front-wheel drive / four-wheel drive |
| Related | Isuzu Gemini/Stylus Geo Storm Isuzu PA Nero |
| Powertrain | |
| Engine | 1.6 L 4XE1 DOHC I4 (US, Canada only) 1.6 L 4XE1W turbo DOHC I4 1.8 L 4XF1 DOHC I4 |
| Dimensions | |
| Wheelbase | 2,451 mm (96.5 in) |
| Length | Base: 4,168 mm (164.1 in) 4,216 mm (166.0 in) |
| Width | 1,694 mm (66.7 in) |
| Height | Base: 1,313 mm (51.7 in) 1,298 mm (51.1 in) |
| Chronology | |
| Successor | Pontiac Sunfire (for Asüna Sunfire, Canada) Chevrolet Cavalier coupe (United States) Chevrolet Cobalt SS (for USDM Impulse RS) |
The second generation Impulse was designed on General Motors's second generation R-body "world car" platform.
GM had commissioned Isuzu to build a replacement for the Spectrum, this time a sportier model called the Storm (Gemini Coupe in Japan). The body design of the Storm was strongly influenced by GM and drew heavily from GM Europe's design submission for the Lotus Elan M100. Under Shiro Nakamura, Isuzu's then head of design, the third generation Gemini sedan was first designed on this platform, and then attention was turned to a sporty coupe to replace the first generation Impulse. Starting with the Storm, alternative front and rear treatments were made, retaining the lozenge theme of the Gemini sedan, and drawing heavy influence from the rear-wheel drive Impulse (semi-concealed headlights with integrated grille as well as hood and taillight styling) while also expanding on the "European look", which later became a central point of marketing the vehicle in Japan.
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). 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) 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.
For the 1992 model year, the Turbo model was discontinued and the base engine was replaced with a 1.8 L (1809 cc) engine, sharing the same bore but with a longer stroke due to the taller engine block. This larger powerplant was good for 140 hp (104 kW) and 125 lb·ft (169 Nm). Both body styles continued into 1992, but very few were produced.
Since the Impulse weighed just 2411 lb (1094 kg) in front-wheel drive configuration and 2732 lb (1239 kg) in all-wheel drive configuration, the turbo engine and all wheel drive combined gave excellent performance.[citation needed]
General Motors, who owned nearly half of Isuzu, also owned Lotus Cars at the time. Lotus selected the 1.6 L engine and transmission from the Isuzu Gemini for the Lotus Elan M100 and a following generation of that engine eventually ended up in the Impulse. Lotus was subcontracted by Isuzu to fine-tune the suspension of the Impulse, through selection of stiffer dampers, larger sway bars, and softer springs. All of the second generation Impulses had the Lotus-tuned suspension.
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 meddling by General Motors forced Isuzu out of the car making market and brought an end to the Impulse.
In the Japanese market, this vehicle was sold as the Piazza beginning in July 1991 through to 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, which was exclusive to Japanese dealerships called Yanase Co., Ltd. under special arrangement, a dealership that sold GM products in Japan.
In Canada, the same models, with minor variations, were sold in the 1990 and 1991 model years. No Impulses were made for Canada for the 1992 model year. In 1993 the 1.8 L model was sold in Canada as the Asüna Sunfire, but only with the hatchback body. Since the phaseout of the Asüna brand in 1993, after only one model year, the Sunfire name moved to a Pontiac, as its version of the third-generation Chevrolet Cavalier on the GM J platform rather than an Isuzu platform.
The second generation Piazza was replaced by Opel Vectra based Holden Calibra in Australia, possibly due to lack of sales of its predecessor while Impulse RS was replaced by GM Delta platform based Chevrolet Cobalt SS in 2004 11 years after The Impulse RS discontinued.