The 1984-89 Carrera, as the final iteration of the original "widebody" normally-aspirated 911, is a good choice for someone looking for an affordable sports car coupled with a high degree of refinement, reliability and sparkling performance.
Comparisons to the 1978-83 911SC are natural, as they share nearly identical bodies and interiors. But the Carrera has many significant improvements, starting with a 3.2 rather than a 3.0-liter engine. The Achilles heel of the 911 engine-hydraulic chain tensioner failure-was solved in 1984. While tensioners on previous models carried their own limited reserve of hydraulic fluid, Carrera tensioners have a steady stream of engine oil fed directly via two small oil lines visible at the rear of the engine. Changing to electronic engine controls in 1984 resulted in lower emissions, higher horsepower and better gas mileage.
Improvements continued in following years. The shifter was redesigned in 1985, reducing lever throw. The air conditioning system, vastly improved in 1984, was improved again in 1986 by redesigning the dash to accommodate larger vents. In 1987, a hydraulic clutch and a new gearbox, the G-50, with improved synchronizers, were introduced.
Carrera engines are durable, but watch for worn valve guides, often more the result of poor maintenance than poor design. Connecting rod bolts have been known to let loose, but this generally occurs on cars that have been raced or autocrossed. Obviously, Carreras with flares, spoilers and faded racing stickers on the doors are not your best choice.
Driving a Carrera is a civilized and comfortable experience, although not as vintage as earlier 911s. As their horsepower comes higher in the rpm band than the 911SC, a generous application of the throttle is required to get to the fat part of the torque curve. These cars are quiet and ride well, so long as no one has added the sport suspension pieces that cause a serious deterioration in ride comfort.
Personally, I prefer the 1987-89 models, as they were the most refined, but the earlier 1984-86 versions can be had for just a bit more than a 9l1SC, and are a better performing car. One of the upsides to owning a 911 is that stock and upgraded performance parts are widely available; one of the downsides is the number of 911 owners who bolt these parts on for a go-fast look to the detriment of the overall performance of the car. Especially with late-model 911s, the factory really knew what they were doing when they set these cars up; unless you're Hurley Haywood heading for Daytona, stock is best.
Porsche 911 Carreras are a tremendous blend of performance and durability for the money. With so many built, the collectible factor for a Carrera coupe is negligible at best, but as a lively daily driver with few vices, these cars are hard to beat.