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Porsche 911 History


1989 Porsche 911 Carrera 4

Bowing in late 1988 for the '89 model year, the Porsche Carrera 4 -- "4" for four-wheel drive -- looked like most any recent 911 except for smoother bumpers and side sills. But appearances here deceived more than usual.

As a direct descendant of the awe-inspiring twin-turbo 959, the "C4" was nothing less than the vanguard for what amounted to a second-generation 911 design. Indeed, it was developed as a separate program, Project 964, and was said to be 85 percent new.

Porsche 911
Subtle but noticeable body alterations marked the 1989 Porche Carrera 4.

That it was, starting with a unique floorpan shaped to smooth airflow beneath the car, plus 959-inspired all-round coil springs with integrated tubular shocks (albeit one per wheel). Rear semi-trailing arms and front struts on lower wishbones continued.

A bore-and-stroke job -- to 100 mm/3.94 inches × 76.5 mm/3.01 inches -- took the production 911's normally aspirated air-cooled flat-six from 3.2 to 3.6 liters. Engineers also applied reshaped combustion chambers, revised intake manifolds, twin-plug ignition, and ultra-high 11.3:1 compression.

In American-market trim, the Carrera 4 produced 247 horsepower at 6,100 rpm -- a gain of 34, and less than 40 shy of the vaunted Turbo -- plus 228 pound-feet of torque at 4,800 rpm. Rolling stock was upsized to suit: 16-inch Bridgestone RE71s, as on the 959. The C4 tires were more modestly sized at 205/55 fore and 225/50 aft but had the higher Z speed rating (good for 150 mph and up).

But, of course, the big attraction was the all-wheel drive that made the Porsche Carrera 4 what one reviewer termed a "people's 959." To be sure, it was drastically simpler than the Porsche 959 system, but that only helped to hold initial retail price to "just" $69,500, a huge saving over the $225,000 it took to buy a 959 -- when you could get one.

Porsche 911
Five-speed manual transmission was mandatory in the Porsche 911 Carrera 4.

The Porsche Carrera 4's all-wheel drive employed center and rear differentials, each with an electrohydraulic multi-plate clutch. Power went forward from the engine to the center differential, then back to the rear wheels via a driveshaft housed within the countershaft of the five-speed manual gearbox; a second shaft sent power to a normal front diff and halfshafts. Both clutches were computer-controlled in response to signals from the four wheel-speed sensors of the first antilock braking system (ABS) ever offered on a "volume" 911, another big C4 attraction.

Though the center diff normally divided torque 31/69 percent front/rear, the computer could vary that through selective use of the clutches whenever the wheel sensors signaled tire slippage (as differences among wheel speeds above a preset threshold). Response time was reported at less than a tenth of a second -- three times faster than the 959 system.

Additional sensors for straight and lateral acceleration allowed the computer to engage the rear differential on lifting the throttle in a corner, thus increasing understeer and hence stability. For safety as well as longevity, both clutches disengaged under braking. A dashboard switch could be flicked to lock the diffs for maximum grip on slippery surfaces below 25 mph; above that speed, the clutches released automatically.

Here was yet another inventive Porsche answer to a customer request -- a more controllable Porsche 911 --and the company was right to term this drive system "intelligent." Further aiding stability were a front suspension modified for zero-scrub radius and new rear suspension mounts designed to vary toe angle with cornering load (like the vaunted "Weissach axle" in the Porche 928).

For straighter high-speed running, the C4's engine grille automatically powered out and up above 50 mph to become a spoiler that increased rear downforce; below 6 mph, it snugged neatly back into the lid. Porsche also claimed the appearance changes gave the C4 a 15 percent lower drag coefficient than previous 911s, plus "zero-lift characteristics at highway speeds."

For all this, some doubted the Porsche Carrera 4's ability. "The new suspension and driveline banish the 911's penchant for tail-out antics," said Car and Driver. "Throw the car into a corner while braking or suddenly lift the throttle at the limit and the Carrera 4 barely rotates; its tail stays solidly planted at all times."

Motor Trend judged real-world cornering "incredible, although the Carrera 4's ultimate...0.84 g is not as high as the Corvette's or even a Pontiac Firebird Formula. What this shows is that lateral-g numbers are just one indication of handling ability. Perhaps a better indication is slalom speed, in which the Carrera 4 [is stellar]."

Though the C4 was no 959 for acceleration, Road & Track clocked a zippy 5.8 seconds to 60 mph and 14.4 seconds at 96.5 mph in the standing quarter-mile -- close to the level of racing Porsche 911s from not too many years before. C/D, as usual, did better: a quick 5.1 seconds to 60 and 13.6 at 102 mph in the quarter.

But the real point was this: "[Porsche has] gained so much balance with the Carrera 4 that we no longer consider its discontinued cousin, the antsy 911 Turbo, a class contender among high-dollar sports cars."

What? The Turbo gone again? Yes, but only from the U.S. market -- the Carrera 4's positive response was a factor -- and only for a few years.

Porsche 911
The "4" in the '89 Porsche 911 Carrera 4 denoted 4-wheel drive.

Check out the complete story of Porsche cars, including these fabulous models:

Porsche 356
Porsche 911
Porsche 914
Porsche 924, 944, 968
Porsche 928 Porsche 959
Porsche Boxster Porsche Cayenne Porsche Cayman

For Porsche prices and reviews from the auto editors of Consumer Guide, see:

  • Porsche new cars
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  • 2007 Porsche 911
  • 1999-2006 Porsche 911
  • 1995-1998 Porsche 911