If you`re looking for a small 4-door sedan with a little guts, thecompact Chevy Corsica fits the bill, providing you go that extra mile-andspend $685-to purchase the optional 3.1-liter V-6 engine. A 2.2-liter, 95-horsepower, 4-cylinder engine replaces last year`s rather anemic 2-liter, 90-horsepower 4-cylinder as standard equipment. The 3.1-liter,135-horsepower V-6 is now optional, replacing the 2.8-liter, 125-horsepower V-6 from last year. We test-drove the 1990 Corsica LT 4-door hatchback sedan. The 3.1 givesit some needed life, just enough of a power boost so that you don`t get leftbehind at the light but not so much that you feel intimidated. The 3.1 was teamed with the optional 4-speed automatic ($540), ratherthan the standard 5-speed manual, and still rated a 19 m.p.g. city and 28highway rating. We found the suspension system a bit surprising. It`s supposedly a ``soft ride`` system, but there was no mushiness or overly pronounced lean, sway orroll in turns. A few changes would be nice, however, such as greater rear-seat leg, head and arm room; a spring-held hood rather than the prop job, which blocks accessto the battery; and firmer brakes with less pedal play. Since Corsica is oneof Chevy`s volume cars, it also would be nice if antilock brakes were madeavailable as an option. Corsica is built on a 103.4-inch wheelbase and is 183.4 inches long.Standard equipment includes power steering, Scotchgard fabric protector, AM/FMstereo with digital clock, side-window defoggers and dual side-view mirrors. LT base price is $9,895. The 3.1 liter and automatic added $1,225. Apreferred-equipment package cost $2,042 and included air conditioning, powerwindows and door locks, cruise control, tilt wheel, tinted glass, intermittentwipers, carpeted floor mats, and power trunk and hood release among the major goodies. Rear-window defogger ran another $160. With options, the sticker read$13,727, plus a $425 destination charge.