The Dodge Shadow was to have been a replacement for the Dodge Omni.

However, Omni sales took off, especially after Chrysler Chairman LeeIacocca came up with a discounted America model. So it was decided thatShadow would be added to the line and not an Omni replacement.

But Shadow hasn`t been setting any sales records.

Enter noted racer and performance car designer Carroll Shelby. Let theman tinker with the Shadow and maybe he can breathe life into the car.

That he has. For 1988, Chrysler has come up with a Shelby CSX versionof the Shadow with an intercooled 2.2-liter 4-cylinder turbocharged enginewith a zero-to-60 m.p.h. claim of 7.1 seconds, a top speed of 135 m.p.h. andan EPA mileage rating of 17 m.p.g. city, 25 m.p.g. highway.

The car is a study in motion. Forward movement with the turbo 2.2 isvery quick. Lateral movement with the quick ratio power steering is veryprecise. Up-and-down movement with the nitrogen gas shock absorbers and firmercoil springs will jar your teeth and knock the pen out of your shirt pocket.

The car also is a study in commotion, and you can`t blame Shelby as you have to wonder when Chrysler will tackle the squeek and rattle problems in itssmall cars.

Quality is proven by reliability, dependability and durability. But the perception of quality comes from the quietness in the passenger compartmentwhen you pass over a tar mark-not the sound of body parts rubbing, scrappingor going to war with one another.

The Shelby CSX is attractive, finished in all black with silver plastic lower skirts and wraparound plastic bumper facia. The large air dam up frontlooks aggressive. The deck lid spoiler adds the right sports touch. The hoodbulge and word ``intercooled`` hints at power. Nice touches.

But there are annoyances other than the noise. The five-speed manual(no automatic) is notchy and not smooth. And the clutch is a bit toospringy. Then, too, the driver`s seat is too low. You feel as if you have tolook up and out over the hood, hardly a position of control in a quick car.

Base price is $13,495 and among the major items includes airconditioning, power brakes, Goodyear Gatorback radials, remote sport mirrors, trip odometer, AM-FM stereo with cassette, digital clock, rear windowdefroster, intermittent wipers, tinted glass and carpeting.