TESTED
Five men, good and true, set out on what seemed like a mission from God: to live with three of the fastest (and reddest) American GTs for two weeks, then sit down to haggle over the findings. A Porsche 928 was anointed to serve as the group’s spiritual inspiration and silver-plated yardstick. Our data-processing machine would systematically sort the raw test results; every annotation of a squeak, rattle, or death-defying maneuver would be culled from the drivers’ logs and fed into the judgment hopper; finally, each editor, armed with half a month’s worth of fact and fancy, would sequester himself to fill out his own Grand Tally Sheet of Subjectivity. The good-better-best final verdicts would spring forth from the voting much as the Ten Commandments fell out of the sky into Moses’ lap. The all-American-GT champion would emerge, and peace would transcend all evil.

At least that was the script. Reality, however, has a habit of going its own dastardly way. We did have a ball hammering these four thunderbuggies up California’s Mount Palomar and down the Ortega Highway. Along the way, we found a lot to love about the Camaro, Mustang, and Trans Am. But we also found a surprising number of traits even a mother would abhor. Toward the end, the Trans Am eked out a one-point victory over the Mustang (plus five points over the Camaro) in the subjective ratings, but that same Pontiac marched smartly to a last-place finish in our fun-to-drive ranking. What’s more, none of the three contenders could drum up a majority when each of the five editors was pressed for a simple “Best GT” nomination.

Sad to say, we have for you no clear winner. Our findings tell us the silver-bullet solution to your GT needs is yet to be made in Detroit. This is not to suggest that the test was a bust; before we sign off, we’ll be happy to confide our most intimate experiences with the four racy-red V-8 GTs. Who knows? This comparo test might tip your balance toward the two-plus-two of your dreams. Then again, it could be the last straw before you rush out and order a four-cylinder station wagon.

____________________



Chevrolet Camaro Z28


Red Speed: Chevrolet Camaro Z28 vs. Ford Mustang GT, Pontiac Firebird Trans Am, Porsche 928
Chevrolet Camaro Z28
RED SPEED.

We ordered our Camaro with the fastest powertrain available—5.0-liter TBI V-8, Turbo Hydra-matic transmission, 3.23:1 axle ratio—even though most of us here at C/D prefer a GT car’s shift lever to be more than a hand rest. To examine the other side of the coin, we ordered the Firebird with the hairiest manual-transmission powertrain offered: the 5.0-liter V-8 (inhaling through a four-barrel carburetor, exhaling through a more restrictive catalyst), the venerable Borg-Warner T-10 four-speed, the same 3.23:1 “performance” axle ratio. Truth to tell, neither powertrain stirred anyone’s soul to ecstasy.


We could carp all day long about catalytic converters and the enemy in Washington, but the essential problem is underhood impotence stacked against 3400 pounds of dead weight. Five liters is an ample piston displacement in the era of $1.50-per-gallon energy. And most manufacturers have found benefits from fuel injection other than simply draining the gas tank expediently (with a capacity of sixteen gallons and a test-trip efficiency of 12 mpg, both the Camaro and the Firebird needed pit-stops every 192 miles). Chevy is currently building five-speed manuals into Chevettes and four-speed automatics into Impalas, so why should the fresh-tech Camaro limp through life with ineffective and unfun powertrains?

When you drive a Z28, there is one engineering breakthrough that slaps you right in the face: this Camaro is not a committee car. The shock valving is so tight that you feel pebbles on the pavement as you back out of a parking space. And the steering response is uncannily importlike to the touch. When your wrists move the wheel, the Z28 responds with the keen linearity that used to be the exclusive province of the better Porsches, Ferraris, and Lotuses of the world. This is not just a lack of the usual on-center null (dead zone) that Detroit has championed for years, but a newfound straight-shot steering response that starts in your garage and runs into the 0.8-g realm. You turn, it turns. There is no slack.

The serpentine switchbacks up and down Mount Palomar demonstrated a clear difference between Camaro and Firebird handling: the Camaro cuts and thrusts with the Porsche, while the Trans Am is noticeably slower on the uptake. To find out exactly why, you have to penetrate the GM hierarchy. Once inside the Chevrolet Division’s perimeter, and at the crux of the matter, you’ll find Fred Schaafsma, a chassis-development engineer who bucked his personal preferences all the way through the convoluted system into production. When you tell Schaafsma the Z28’s ride over expansion joints makes your teeth ache, he replies that there are base Camaros and a Berlinetta upgrade for the comfy-cruising set, while the Z28 was planned from the start as the bare-knuckle street fighter. One natural foe was the Trans Am, so Schaafsma spent the money and effort to stiffen the Z28’s step until he was sure it would walk around the Pontiac, and just about any import you could name, in handling. As it stands today, the Z28 and T/A share plenty—powertrains, basic body structures, wheel width, tires, even anti-sway-bar diameters—and Schaafsma will speak of the key chassis differences only in roundabout terms: stiffer rear springs, an unspecified subtlety in the rear suspension, and six particular braces and bushings in the front end. These latter pieces make the Z28 feel steel-bowstring taut over bumps, while the Trans Am is much more resilient. They also help make it the demon of the slalom run, where the Trans Am is merely excellent. Both cars still have a way to go in steering feel, however. The Porsche along for the ride had a higher effort at the wheel rim and a far more tactile touch with the road, two traits we admire in any context.


Some other aspects of the driver’s interface with the chassis also need attention. The extra-cost Conteur driver’s seat is as comfortable as a pin cushion: the too-aggressive under-thigh bolster acts like a leg tourniquet even in its most retracted position, and the steel wires that serve as the side bolsters’ skeleton poke through painfully as cornering loads build. We prefer the Camaro’s instrument panel to the Firebird’s, but can’t understand the nickel-sized gauge ports or the hard console edge that hates the driver’s right thigh.

It should be obvious by now that we have an amalgam of emotions for the Z28. Our fun-to-drive favorite (even with the lackadaisical automatic transmission), it fell to second place in acceleration and all the way to the bottom in the subjective totals. The makings of a great car are here, but the development program is far from over.

____________________



Ford Mustang GT

The flier from Ford was crude and comparatively unwieldy in several of the decathlon events that composed this GT olympics, but in terms of sheer visceral appeal, it’s right up there with the Porsche. Press on the Mustang’s gas pedal, and great things happen. An authoritative growl from under the hood is accompanied by screeches of rubber at the back of the car. This Mustang is at the moment the quickest machine made in America, and our internal sources at the Ford Motor Company suggest that efforts are afoot to keep Mustangs and Capris that way.


The Mustang is hardly a one-dimensional quarter-mile specialist, but it clearly lacks the chassis to compete with either Porsche’s finest or the latest science from GM. What the Mustang does enjoy deep within its four-year-old, Fairmont-derived underpinnings is an ideal basic size. It’s ten inches shorter, three inches narrower, and a hefty 400 pounds lighter than the new GM kids on the block; as a result, it feels nimble and eager to get the job done. The body’s comparatively blunt shape doesn’t benefit from the recent intense aerodynamic-drag efforts, but there is a compensating benefit: the less-sleek Mustang offers the only real back seat in the test and the roomiest luggage compartment.


The Mustang’s front seating is also a credit to the GT class. Instead of attempting to reinvent the sport seat in-house, as Chevrolet (actually Fisher Body) has done with the Camaro, Ford shopped at the acknowledged orthopedic experts—Recaro—and fulfilled its obligation once and for all.

The not-so-satisfying phases of Mustang life have to do with handling. The rack-and-pinion steering is one of those pinky-finger jobs where actual road feel is not allowed. Down at the business end of the steering linkage, Ford has gone a bit skimpy on tire size, so the smallish Michelin TRXs have all they can do to generate a feeble 0.75 gs’ worth of grip on the skidpad. The engineers have done a fair job tuning the Mustang’s ride—judged better than the Camaro’s, not as plush as the Trans Am’s—and their roll-stiffness distribution has set the handling commendably close to neutral steer. One small problem that’s left is that there is not enough anti-sway bar to flatten out the proceedings through life’s ess-bends.


A bigger concern is a woefully inadequate rear suspension. What we have here is the Peter Principle applied to four-bar linkages. The Mustang’s rear suspension started life in the Fairmont, where it worked just fine. But with 240 pounds-feet of torque multiplied by the manual transmission, those four stamped-steel links are burdened well beyond their level of competence. A set of windup limiters has been Band-Aided into the system for 1982, but they’re only half as effective as a full fix would be. In left-hand sweepers, the gas pedal acts as a power-oversteer switch: put your foot down (in the lower gears) and the tail slips out. That smooth two-step unfortunately turns into a jitterbug in right-hand bends, where power hop conspires with the transmission to make life difficult. The Mustang’s box shifts better than the Pontiac’s and the Porsche’s, but on the road it acts convincingly like a five-speed with a missing third gear. In mid-speed right-handers you’re confronted with a nasty dilemma: to power-hop your way around in second, or to chug through in third?

We do expect some attention to these and other problems in the Mustang as Ford tools up the guts to go behind the GT badge, but in the meantime, there’s no denying the terrific value here. You can still roll a hot Mustang (or Capri) out the door for less than ten grand. In terms of power-to-weight ratio for a price, there’s nothing that can touch the Mustang from GM, Germany, or even Japan.

Pontiac Firebird Trans Am

This test makes one thing perfectly clear: Trans Ams are not what they used to be. The proud bird on the hood now broods over Chevrolet-built engines. The mean and macho WS6/7 has been clipped back with refinement, its ride/handling balance skewed noticeably more toward comfort than the rival Chevrolet. And while the old T/A was a flapped and spoilered war bird, the new species is more the pretty peacock. Its long, shapely snout and sleeker roofline slide through the air without a ruffled feather.


As with the Chevy in this test, the Firebird has problems. Something is desperately wrong when a Nissan Stanza econosedan beats the ballsiest four-speed T/A to 60 mph. And almost all the same basic traits that have to do with using the Firebird’s stick shift are miserable. A courtesy light is quite inconveniently located in the already tight space over your clutch foot; nine shifts out of ten, you snag the sole of your shoe. Heel-and-toeing is difficult, if not impossible. The transmission linkage is a high-effort, low-precision device that’s annoying to use. With no fifth in the box, on the highway you feel you’re stuck in an intermediate gear.


The four-barrel V-8 is a torquey and responsive price mover at the low end, but a run through the gears is really just four short spurts instead of one sustained burst of enthusiasm. Thanks to the restrictive pellet-type catalyst packed into its pipes, the LG4 engine’s power curve wilts on cue right after its 4000-rpm peak. You can force matters to the 5000-rpm redline—in fact, you can cruise at that speed in top gear (116 mph) on about two-thirds throttle, thanks to the tidy aerodynamics—but there’s so much driveline coarseness fed up and into the car at higher rpm that it rarely seems worth all the commotion. Will the Japanese have to bring out six-speeds to convince GM that a nice, easy-shifting, properly ratioed five-speed is part of doing business these days?

There are reasons to celebrate the new Firebird. The exterior sculpturing is an absolute knockout, and we hope and pray the sales department doesn’t ruin the artwork with its usual demands for scoops, stripes, and more bird droppings. The chassis is a satisfying accomplishment, admittedly not as crisp as the Camaro’s, but a maneuverable piece just the same.

Unfortunately, something went haywire in the interior. The base front seats are essentially J-car components—not bad for a compact, but hardly up to snuff in a $13,000 GT. Pontiac does, make that did, offer a special Recaro package that unfortunately tied the T-top roof into the bill of materials, running the tab for this one option to $2486. The 2000 that were planned for production through May were promptly snapped up anyway, so we’re back to the J-car seats, which aren’t rated for the 0.81-g cornering capability of the new Trans Am.


Then there’s the instrument panel. The far-out aerospace look was supposedly the goal, but in execution the Trans Am never quite breaks out of the Piper Cub realm. Allen-head screws are sprinkled about unconvincingly, and the instrumentation is belittled by huge plastic bezels. The steering wheel, a nice, classic three-spoke design, suffers from the heavy-handedness of the plastic-allen-screw proponents. The view over the rim and down the steep hood is a joy to behold, however, particularly if you select a Firebird without the asymmetric “power” bulge.

In the American tradition, there are plenty of ways to spec out a Firebird; as a matter of fact, the powertrain from the Z28 in this test is also available at your local Pontiac dealer. If you find even that eminently resistible, there is a ray of hope for the future. We understand better seats, a five-speed transmission, and stickier tires will enter the Trans Am’s options list within the year.

____________________



Porsche 928

The Porsche was a terrific reference in this endeavor because, in our collective opinion, it is nearer perfection than any other GT ever built. This is not to say that we’re scolding Detroit for denying car freaks the $40,000 made-in-America exotica they so richly deserve. To the contrary, Camaros, Firebirds, and Mustangs are already expensive enough, but they clearly have room for improvement. We see the 928 as the right kind of goal for future efforts.


Where Porsche has them all licked is under the hood. Yes, it’s powered by a very expensive, all-aluminum, overhead-cam V-8, but there’s far more spirit here than simple money can buy. That engines are for making power is a fact of life at Porsche, but one that seems to be lost on most engineers in Detroit. When you step on the gas pedal, the 928 rushes smartly for the 6000-rpm redline with no timeouts to remind you that this is a gas-mileage motor, or a prime mover tuned only for the EPA dyno and the first 30 feet away from a stoplight.


Five nicely spaced transmission ratios help keep the underhood spirit alive, but here you find the 928’s Achilles’ heel. The 928’s shift linkage generated widespread bad reviews to the extent that most of us are avowed 928-automatic fans.

Although the domestics are knocking on Porsche’s door in handling, the 928 has a very distinct edge you won’t find in the test results. It feels much better through the steering, because forces from the tire patches are delivered to your finger tips to tell you just what’s going on. The 928’s attitude approaching the limit is also far more sensitive to the driver’s commands than the other three cars in this test. No matter how hairy the maneuver, there always seems to be a little agility left in reserve. Adjustments to the throttle generate an amazingly adroit response: lifting ever so slightly causes the nose to tighten its cornering arc a notch at a time without the usual slewing and sliding at the back of the car.


If we were chief engineers for a day at any domestic division interested in the GT business, the very first $40,000 out of the budget would go for a 928. What this car has is too special to be the private reserve of the ultrarich forever.

Conclusion: The perfect GT is yet to be built. The Porsche 928 has just about everything necessary to qualify except an affordable price. We could be quite happy with the Mustang’s seating and acceleration, the Camaro’s handling, the Trans Am’s aerodynamics and ride comfort, if all these qualities could be neatly wrapped in one package. Such a car is clearly within the realm of possibility. And if it doesn’t come from Detroit soon, you can be sure one will head our way from across the water. Just watch for an ominous speck growing in the glare from the Land of the Rising Sun.

____________________



Chevrolet Pacing, As You Like It

Simplicity is a virtue of great complexity, as anybody who has built cars will tell you, but it's often difficult to con*vince the guys in the leather chairs that the simple ap*proach is the best way to make a big splash. They usually seem to feel that the more flash, the bigger the splash. Re*cent Indianapolis 500 pace cars have been so highly modi*fied that they were also highly likely to provide one big flash and altogether the wrong kind of splash.

Providing pace cars for the Indy 500 is a risky business. This is, after all, the most-watched automotive event in the world—a third of a million people mashed fanny to fore*part in Indiana and tens of millions more watching and lis*tening around the world. So here come you, the Michigan mogul, already under fire for falling sales and so-so quality control, and you're represented, as anybody still alive on Memorial Day weekend can plainly see, by this pace car of yours, and it's got to start and run and go flitting in and out of the pits on command to lead all these race cars around in front of all these people. You don't want it to swallow its starter or hiss out its coolant or bolt for the wall or sprinkle its engine all over the front straight. Extremely bad form, you know.

If you happen to be Chevrolet and you've bid yourself into providing a matched set of Camaro Z28s to pace the 1982 Indy 500, you take one look at the overengineered recent efforts of others and you get John Pierce on the phone. John Pierce is in Product Promotion Engineering at your engineering center, and you say, "John, build us a pace car, not a prototype hand grenade." He dives head*long into your corporate book of performance parts, ap*propriately entitled Chevrolet Power, and comes out with a pair of Z28s boasting 50 percent more horsepower than stock, but no bad habits.

What Pierce has put together is Chevy's proven small-block 5.7-liter racing V-8 engine, an animal as reliable as sun in the Sahara and further tamed with your basic street-option crossfire fuel injection, which proves surprisingly compatible with the hefty and yet feathery mechanicals underneath it. The familiar all-aluminum racing block is fit*ted with aluminum heads, big valves, hydraulic lifters, the high-output cam first developed for the 327s almost twen*ty years ago, forged aluminum pistons, and heavy-duty crank and connecting rods. The compression ratio is 11.0:1 (versus the stock 5.0-liter's 9.5:1) and output is up from 165 horsepower to an easy 250, estimated.

The catalytic converter has been left on the shop floor and the heavy cast-iron exhaust manifolds have been de*leted in favor of thin-wall headers. The engine itself weighs 120 pounds less than its cast-iron counterpart, and the total saving means the pacing Z28's weight distribution comes in at very nearly 50/50. Optional four-wheel discs are used, and the stock Z28 suspension is retained. The single change in running attire is a switch from 215/65R*15 tires to shaved Goodyear P245/60R-15s. European-export headlamp covers and a 140-mph speedo are the only other additions of note beyond the roof lights, radio system, and an ABC TV camera hidden behind a tail lamp.

Cruising at 90 on the banked, glassy surface of the big speedway is effortless. The engine loafs, but it's snugly ready to rush the three-speed automatic forward at a touch. Danny Ongais took one of the cars out and declared a 120-mph average to be no more than a two-finger steer*ing operation (even if his fingers are worth about a dozen of anybody else's). The shame of it is that this effortless performance is available to no one but pace-car drivers (at least not from the showroom). And these all-aluminum en*gines' look so pretty and tidy and clean. For once, simplicity hasn't required great complexity. This obviously will have been a great comfort on race day for those of you who occupy Chevrolet's leather chairs. —Larry Griffin
____________________




Aerodynamic Annotations

Aerodynamics is all the rage in Detroit these days. The manufacturers have finally discovered the benefits of a clean shape, and they're trumpeting their achievements with the zealous fervor of new converts. Pontiac is even claiming that the new Firebird Trans Am is the world's slipperiest production car, with a drag coefficient of 0.31. While we can't name a car with a lower Cd, we are a bit skeptical about this figure. We have a basic distrust of drag coefficients because they inevitably mislead. Furthermore, GM has never reconciled the Trans Am's 0.31 drag coeffi*cient with the Camaro Z28's 0.37 figure.

That's a large difference for two very similar cars. The Trans Am does have retracting headlights, which are not only sleeker than the Camaro's but, more important, also allow a lower hood line, by nearly two inches at certain points. The Trans Am's flush wheels are also an advan*tage, albeit a small one (the Cd benefit is less than 0.01, according to sources within GM). In other respects, how*ever, there's not much to choose between the two cars. The front-spoiler designs are completely different—the Z28's is on the leading edge of the bumper, while the Trans Am's is just forward of the front wheels—but nei*ther arrangement is clearly superior. Ditto the rear spoil*ers, which, though contoured differently, are virtually identical in effectiveness (both trim Cd by less than 0.01). It's hard to see where the total of these differences adds up to a 16 percent advantage for the Trans Am.


Differences in aerodynamic-drag coefficients are often a result of wind-tunnel inconsistencies, but both of these cars were tested at the same GM facility in Warren, Michigan. This doesn't eliminate all the wind-tunnel variables, however. Most cars have less drag when they sit lower. Recognizing this, Pontiac says that the 0.31 figure was ob*tained at "EPA coast-down height," though it makes no at*tempt to explain what that means. Also, production tolerances in springs and other suspension components may be used to a manufacturer's advantage during testing.

Another significant source of aerodynamic variation is body-panel fit. Close-fitting, flush seams are better than wide, protuberant ones. Sloppy fits not only upset airflow over the car, but can allow harmful internal airflow as well. For example, eliminating airflow through the duct in the Z28's front spoiler improves its Cd by 0.02. In fit as in ride height, two cars can be within production tolerances, yet be quite different to the wind.

Our coast-down testing is also affected by these vari*ables, but at least we test production cars, not hand-mas*saged prototypes. Furthermore, the coast-down test is a real-world situation, with a moving car, a fixed ground plane, and rolling tires; in a wind tunnel, everything but the airstream is stationary. In testing the Trans Am and the Z28 back-to-back, we found that the Pontiac required 8.0 horsepower to overcome aerodynamic drag at 50 mph, while the Z28's aero horsepower is 8.5. Since the frontal areas are nearly identical, this difference has to be a result of the Trans Am's lower drag coefficient.

This doesn't mean that the 0.31 drag-coefficient claim is less suspect, but it does prove—to our satisfaction, at least—that the Trans Am is a significantly cleaner shape than the Z28. —Csaba Csere

____________________