his text originally appeared in the August 1984 issue of Road & Track Magazine.
Even among the best-remembered names in automotive history, a few stand out as truly special. Silver Ghost, XK-120, SSK, Twin-Six and possibly the best known of recent machinery, the GTO. There were two GTOs, of course, the original from Ferrari and the imitator from Pontiac. Though a comparison of the two is ludicrous, each was at the head of its class.
The Ferrari was developed for the Manufacturer's GT Championship, which it won in 1962, 1963 and 1964. Those of us involved with the real GTOs were incredulous that Pontiac would adopt the name for its muscle car. For one thing. Gran Turismo Omologato is Italian and Pontiac could at least have used the English form, “Grand Touring Homologated” or GTH. But then GTH doesn’t quite roll off the tongue in the same way.
Though Pontiac may now be light years away from automobiles like its GTO, Ferrari has a new one that very nicely updates the concept of the 1962 original and provides the sort of GT class-winning chassis the company hasn't had since the 365 GTB/4 Daytona. I had the opportunity to make a back-to-back comparison of the new and the original Italian GTOs at Ferrari’s Fiorano test track in Italy. The 1962 GTO is chassis number 385 1GT and owned by Dr Fabrizio Violati of Rome. As a car that’s used for vintage race events, Violati’s GTO is a very good example of the first series of that model. The 1984 car is one of the first three made and is the initial development prototype.
Two hundred GTOs will be built to meet FISA’s Group B homologation requirements. These are completely finished road cars that can even be fitted with an $1800 option package that includes an AM/FM radio/cassette, air conditioning and electric window lifts. Or you can buy your $83,400 GTO (in Italy, minus their taxes) without these options and prepare it for racing or rallying. Under Group B rules, Ferrari will also be allowed to a further 20 “evolutionary” examples that must maintain the same basic body shape and the 2420-lb minimum weight, but can be more fully developed as competition cars for the track or tarmac rallies such as the Tour de Corse.
Ferrari’s 308 GTB was used as a starting point for the GTO, but little remains of the production 308. Why even start with it? When the project began in 1982, time constraints and other practical considerations made it advantageous to begin with an established design. Besides, from a commercial standpoint the GTO will enhance the image of all 308s.
The GTO looks like a 308 GTB with fender flares, larger spoilers front and rear, tall outside mirrors, four extra driving lights in the grille and a more broad-shouldered, masculine appearance. Pininfarina, which designed the body for the 308, is also responsible for the GTO, refining the car’s aerodynamics in its wind tunnel. So often the original of a design has the most pure, lasting appeal, with subsequent variations rarely improving things. In this case, the opposite is true. In my opinion the GTO looks like the 308 I would have preferred right from the start. The new car—with its three slanted cooling slots, inherited from the earlier car but now on the rear fenders—has an altogether more business like look to it, form following function to an even greater degree than in the 308.
There are other differences between 308 and GTO than just reshaping, because the body panels of the GTO aren’t steel like the current GTB, but fiberglass as in the first few 308 GTBs. In addition, the hood is made of Kevlar, with the roof done in Kevlar with carbon fiber. Underneath the skin, the firewall has Kevlar, Nomex and aluminum honeycomb. This fiberglass-and-composite body offers the best strength for the least weight, but in the 20 evolutionary cars Ferrari will go still further with more composite panels, using up the minimum weight in other ways, possibly as a roll cage or dry-sump system.
Under this lightweight body is a completely new all-steel tube frame made necessary by both the GTO’s purpose and new drivetrain layout. Though theoretically it’s an option, each GTO will have a roll bar. Suspension doesn't change in principle, both ends having systems based on upper and lower A-arms with coil springs/Koni shocks and anti-roll bars. The suspension arms are of tubular steel. Quite naturally there are ventilated disc brakes at each wheel. The tires are Goodyear’s Eagle VR50 type, 225/50VR-16s at the front and 265/50VR-16s at the back, mounted on modular alloy wheels, not quite so romantic perhaps as the Borrani wire wheels on the original GTO, but a great deal more functional. No more long panicky pit stops with broken spoke ends jamming wheels on during an otherwise straight forward change. Steering is by rack and pinion. All these chassis pieces are subject to change, of course, with the evolutionary GTOs and for customer racing cars.
Nice as all these changes might be, the true soul of this new GTO, just as in the original, is the engine. Ferrari purists will probably moan that this GTO doesn't have a V12, and I admit that the sound of the 1962 GTO may be more exciting than the turbocharged V8 of the new car. but that’s the only point of superiority I'm willing to concede.
The GTO’s V8 is in the more orthodox longitudinal position rather than the 308's transverse location. The reasons for this start with the plumbing for the turbocharging system. It would have been a white-hot nightmare routing the exhaust from the bulkhead side. But the configuration is also simple and offers a more proven layout that can be quickly and easily serviced (including gear ratio changes) in the rush of competition, even more critical in rallying than racing.
Needless to say, turning the engine 90 degrees used more space than was available in the standard 308 wheelbase, which is now increased 4.3 inches. to 96.5 inches.
Ferrari has based the engine block and heads of the GTO on those from the production 308, while the turbocharging/induction system is inspired by the Formula 1 program. Displacement is 2855 cc—just 72 cc less than the 308—with a bore and stroke of 80.0 x 71.0 mm (3.15 by 2.80 in.), so it’s essentially a turbocharged 308. The capacity is dictated by FISA, which rules that the displacement times the turbo factor of 1.4 cannot exceed 4000 cc for the GTO’s class; with the GTO that works out to an equivalent of 3997 cc. And Ferrari has used it very effectively, getting 400 bhp at 7000 rpm and 366 lb-ft of torque at 3800 rpm. In competition form we could probably expect something on the order of an additional 100 bhp.
All this begins with the aluminum block and twincam, 4-valve heads of the production 308, appropriately modified for their new job. The cylinder liners are still of nickel-treated aluminum, with new pistons for the 7.6:1 compression ratio, lower than the 9.2:1 of the European 308 Quattrovalvole. These pistons are now cooled with an oil spray from beneath, and the crankshaft has been redesigned to accommodate greater loads.
The most important engine difference is the turbocharging system. The twin turbos are from the Japanese firm IHI and were chosen for their minimal inertia. One of the aims of the V8 design was to keep the power band wide and flexible for city and high-speed use. The quick spool-up of a pair of turbos versus one large one helps reduce undesirable lag. The 11.3-psi maximum boost is kept in check by a standard wastegate.
Controlling the fuel and ignition of the V8 is an electronic system developed by Weber and Marelli, the same firms that did the same jobs non-electronically on the original GTO’s V12. Sensors take such inputs as coolant temperature, boost and ignition advance, run them through an onboard computer and use the results to regulate fuel flow and ignition timing. A similar system was used by the Ferrari FI team at the Brazilian Grand Prix this year. This V8 can easily be seen as a pair of inline four-cylinder engines, each with its own induction, turbocharger, ignition system and air-to-water intercooler from Behr, which makes the intercoolers for Ferrari's GP cars.
A new five-speed gearbox was designed for the GTO and, in GP racing fashion, it’s to the rear of the differential. Behind the engine is an 8.5-inch two-plate clutch. The clutch shaft goes rearward past the ring gear to the end of the drivetrain. There, a pair of quick-change idler gears transmit the power to the gearbox, then forward to the differential. This design allows the engine to be placed 2.7 inches lower in the chassis, dropping the center of gravity and aiding in improving roadholding.
On first seeing the horsepower and torque figures for the GTO V8. it doesn't seem we’re getting two decades of progress over the 3.0-liter, 300-hp V12 of the 1962 GTO. However, one must remember that the original GTO, with all its flexibility from quite low revs, still developed its power over a very narrow band. This new car, on the other hand, with slightly less displacement (and turbocharged, of course) gets another 100 hp and a much higher torque figure over a broader range. In fact, it's amazing what kind of work this engine will do at even 3500 revs. At that rpm, for example, the new engine has already developed 85 percent of the maximum power available in the original GTO and it just gets better from there. At both 6000 and 7500 rpm, the V8 is developing about 98 percent of its maximum power, the figure of 400 hp coming roughly halfway between these engine speeds.
It’s obvious the new GTO is a turbocharged car because of the disproportionate increase in power one senses as the revs mount. At the same time, it’s remarkably free of the bothers so many high-performance turbo cars have today, such as slow initial throttle response, followed by an unwanted rush of excess power. The GTO just takes off headed for such intermediate times as 5.0 seconds to 60 mph, 11.0 seconds to 100 mph and on to the factory’s claimed top speed of 305 km/h (189 mph). The progressiveness of the GTO’s flow of power and its remarkable control are as good or better than anything I’ve ever experienced. In the lower gears, for example, on twisty roads up to 80 mph or so, the fact that the engine gains an additional 240 hp between 2500 and 5500 rpm could make things quite uncomfortable. The trick here is to simply poke it into the next higher gear and use larger throttle openings. This not only gives you a wider range of conditions under which power is available, but also tends to diminish any abruptness. One of the most delightful aspects of the car is that despite the added horsepower and greater mid-range torque, the GTO has a light, nimble feel and not the heavy, intimidating nature of, say, a Boxer or Countach.
To go with this lovely engine is road-holding of a very high order. The grip of the car on the road is phenomenal and noticeably increases with speed. In fact, it's difficult to induce unwanted oversteer in any gear. On the very slowest turns, such as a hairpin where the tendency is for the front end to push, power oversteer can be used to good advantage, but with little fear of spinning the car. In fact, few cars I have driven can be gotten so far around and still be considered under control. Even though at Fiorano it’s difficult to do any truly high-speed cornering, it’s not hard to imagine what this machine would be like at Le Mans ... stable through the kink on the Mulsanne Straight and fast through the turn before Indianapolis, yet still able to storm through the twisty bit before the Ford Chicane. Unfortunately, rain the night before our test session left Fiorano’s skidpad a reflecting pool—good only for pondering the GTO’s quantitative handling potential. Further, the circuit’s narrowness (and the proximity of its expensive timing lights that outline the surface about every 30 feet) prohibited our usual slalom test. However, we’ll have an opportunity soon to perform these tests and report the results.
The GTO’s steering is light and precise, but, of course, the car isn’t that heavy relative to other ultra high performance automobiles. A track like Fiorano puts tremendous demands on a car’s brakes and the GTO’s proved to be of the same high order as the rest of the package. Indeed, our 240-foot stopping distance from 80 mph is among the very best we’ve ever recorded. The 1962 GTO, good as it was in its day, has quite heavy steering and braking, and a comparison with the new GTO is unfair.
All this is accomplished from an interior that's the essence of luxury compared with the spartan GTO of 1962. Our Sebring class-winning car that year didn’t even have a dashboard per se, while the “production" GTO of 1984 has comfortable leather seats, a carpeted floor and even a complete stereo system. And the instruments—a tachometer, speedometer and gauges for turbo boost, oil pressure, coolant temperature and fuel level—are set in a proper dashboard.
So there are the two decades of progress. In total, the new GTO is miles ahead of its 22-year-old predecessor in performance. And yet it offers the option of air conditioning and Leoncavallo’s Pagliacciin full stereo. The potential of the 20 evolutionary GTOs should raise the name even higher up the automotive honor roll. As pleased as I am to see Ferrari competing strongly in F1, I’m delighted they will once again have a Gran Turismo car with true competition potential. That’s what the name GTO meant in the first place.
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