two-door bodystyle. Only in March 1990, four-door versions of the S-10 Blazer and Jimmy were introduced as 1991 models, with a greater wheelbase and length. While significantly smaller in all dimensions than the K5 Blazer, interior space was comparable or larger thanks to better packaging - the luggage area, for instance was rather than the of the older model. Base power was provided by GM's 2.0 L OHV four-cylinder engine, producing . A 2.8 L, V6 was offered as an option (coincidentally this engine was also used in Jeep's competing Cherokee until 1987). Due to emissions laws, a 1.9 L gasoline inline-four built by Isuzu was offered as the base model engine in California in place of the 2.0 L engine, while an Isuzu 2.2 L diesel engine (also used in the S-series pickups) producing was offered as an option. The 1.9 and 2.0 L gasoline fours and the 2.2 L diesel were dropped after 1985, replaced by the larger 2.5 L Iron Duke engine. The V6 was refitted with a throttle-body fuel injection system for 1986 in order to improve performance and fuel economy. In order for it to keep being competitive, the Blazer and Jimmy received a new V6 option for 1988 (also used with the Astro/Safari vans, short wheelbase G-series vans, and light duty C/K-1500 trucks), based on the Chevrolet Small-Block V8 engine, producing a respectable . Power output was increased to for 1989, while the four-cylinder engine was dropped. The 2.8 L V6 was discontinued after 1990, making the 4.3 L the sole available engine. A 5-speed manual transmission (Getrag 290/Hydramatic 290/5LM60, sourced from the GMT400) was added to the option list, replacing the Borg-Warner T-5. In March 1990, 4-door versions of the S-10 Blazer and Jimmy were introduced as a 1991 model; the 4-door had a 6.5 in longer wheelbase (2-doors had a 100.5 in wheelbase - six inches (152 mm) longer than the Ford Bronco II) and a one-piece front grille with a painted black insert (1990 two-door S-10 Blazers and Jimmys had the three-piece grille). This new grille also did away with the separate metal filler panel under the grille, since the grille is taller and took its place. Early production models between March and August 1990 were initially available as a four-wheel drive only; 2WD versions commenced production around Summer 1990. This came just months ahead of the introduction of the Ford