(from GM Press Release) Combining the vintage style of the 1966 Olds Toronado with the contemporary punch of a 1,070-horsepower twin-turbocharged V-8 GM Performance Parts prototype crate engine, Jay Leno cruises Burbank , Calif. in a sophisticated blend of classic style and cutting-edge technology.
Equipped with numerous parts under consideration by GM Performance Parts (GMPP), the Toronado has a factory-look appearance, with restored bodywork and a mostly stock interior – but under the sheet metal lies a modified C5 Corvette chassis and suspension, along with the sophisticated twin-turbocharged prototype crate engine and a Corvette rear transaxle.
“This is a vintage American answer to expensive European grand tourers,” Leno said. “There is an unmistakable character here that exemplifies confident American car design – and it just happens to be backed up by, oh, a thousand horsepower and the reflexes of a Corvette.”
The car was built at Leno’s Big Dog Garage, in suburban Los Angeles , under the direction of builder Bernard Juchli.
Leno was attracted to the Toronado for its distinctive styling and historical significance – it was the first high-volume front-wheel-drive car produced by GM. It was originally powered by a 425-cubic-inch V-8 that was connected to the front wheels via a robust transaxle, a combination which pre-dated the industry’s almost universal conversion to front-wheel drive by about 15 years.
The groundbreaking styling was the work of GM’s famed designer Bill Mitchell, who styled an automobile that was lauded by critics when new and has been remembered as one of the most important design statements of the 1960s.
“It was a forward-looking car almost 40 years ago and its style still looks contemporary today,” Leno said. “The prominent fender flares are features you see on countless new vehicles, so the car still has a smart, contemporary look when you apply current trends like 17-inch wheels and tires – it’s a natural fit.”
Leno’s car, while still powered by a 425-cubic-inch engine, sends power to the rear wheels by way of a C5 Corvette transaxle. In fact, a C5 chassis was modified and grafted beneath the Toronado’s bodywork. The Corvette’s sturdy hydroformed chassis was cut at the firewall area and lengthened 14 inches to the rear, which pushed the wheels into position within the car’s fenders. The basic suspension – aluminum double wishbones with a transverse leaf spring, both in the front and rear – was retained, although new springs and Bilstein shocks were added to fine-tune the car’s handling and support the Toronado’s heavier steel body.
The car sits on contemporary 17-inch Bridgestone Redline tires and custom aluminum wheels designed to evoke the look of the original hub-prominent versions. What wasn’t altered, however, was the car’s bodywork or color. The original-look Trumpet Gold hue was reapplied with a modern base coat/clear coat paint system from BASF and the car’s body was restored to its factory-original appearance.
“The Toronado has a bold design – there was nothing like it then or since, and we didn’t want to mess with Bill Mitchell’s original styling,” Leno said. “Every piece of original trim has been restored or replaced to make sure the car looks authentic.”
Two hairdryers, no waiting
Reaching the 1,000-horsepower threshold for the Toronado’s engine was achieved with an intercooled twin-turbocharger system pumping 19 pounds of boost into a GM Performance Parts prototype 425-cubic-inch small-block crate engine. Developed in conjunction with GM Performance Division, the engine uses a modified aluminum block and cylinder heads from the Cadillac CTS-V racing program. They’ve been reconfigured to work as a high-performance street engine – a must for Leno, as he intends to use the Toronado as a daily driver.
Although not currently offered for sale by GM Performance Parts, the high-performance 425 engine serves as a real-world evaluator for potential new products.
“All the basic elements of this engine will soon be available in either the GM Performance Parts catalog or elsewhere in the GM parts system,” said Will Handzel, group manager, GM Performance Parts. “Participating in projects such as Jay’s Toronado gives GMPP the opportunity to ‘clinic’ high-performance combinations and evaluate ideas we might not otherwise would have considered. This engine made 1,000 horses without too much trouble, and it already has us thinking of future crate engine possibilities.”
A GM Performance-spec’d forged steel crankshaft and connecting rods are used on the bottom end of the 425 engine, along with custom forged aluminum pistons. When pushing up toward the CNC-ported aluminum cylinder heads, the pistons deliver an 8.3:1 compression ratio – a relatively low compression ratio required to ward off detonation in a turbocharged engine. The cavernous heads channel the huge volume of air generated by a pair of ball bearing-type turbochargers to the combustion chambers. High-flow GM Racing fuel injectors are used to match the airflow and a GM prototype camshaft actuates the valves – the camshaft is a high-performance item that may just reach production sooner than later.
High, prominent mounting of the turbochargers makes them impossible to miss when the Toronado’s hood is raised. They generate airflow that passes through a pair of intercoolers (mounted behind the radiator) and through a pair of GM mass air meters, where the pressurized air supply merges and enters the engine through a GM Gen IV V-8 90-mm electronically-controlled throttle body and composite intake manifold. A custom exhaust system was fabricated from scratch-built, stainless steel headers and is routed through a custom-fabricated stainless steel exhaust system.
In keeping with the car’s high-tech nature, as well as leveraging the C5’s unique chassis layout, the Toronado’s engine is connected to a beefed-up Hydra-Matic 4L60-E four-speed automatic via the Corvette’s unique rear transaxle. The transmission actually is attached to the rear axle rather than the engine; it also was strengthened to handle the 425’s considerable torque. As the C5 chassis was lengthened by 14 inches, the driveshaft and torque tube that link the engine and transmission required modification. Juchli fabricated a new torque tube section, while a racing-style, 3.5-inch-diameter drivershaft was built by a local specialist.
Because the electronically controlled transmission doesn’t have a traditional speedometer cable, a special converter – similar to those used by many street rodders who adapt late-model, electronically controlled transmissions to their vintage cars – is used so the Toronado’s unique drum-style speedometer operates accurately.
There’s another advantage to using the Corvette transaxle: it creates better front-to-rear weight balance. The original Toronado’s heavy front engine/transaxle combination placed a large mass over the front wheels, rather than spreading it along the driveline and out to a rear axle.
Basic black
From the ground up, Lear customized the entire interior. Like the bodywork, the Toronado’s all-black interior is mostly stock in appearance, right down to its steering column-mounted automatic shifter. The car originally was equipped with a front bench seat, but it was removed to make room for a driveline tunnel required to make room for the chassis’ torque tube. A pair of leather-covered seats was crafted to mimic the design of available bucket seats. The rear seat also was re-covered in leather and modified slightly to accommodate the driveline tunnel.
A center console was crafted to fit between the bucket seats. It is styled to appear vintage factory-original and serves to cover the driveline tunnel. The dashboard is original, although a couple of instruments have been added to more accurately monitor the turbocharged engine’s operation.
Even the Toronado’s trunk was revamped. In it, a custom fuel cell is fitted, as is a pair of high-volume electric fuel pump, a single 12-volt battery and a custom air conditioning system designed by Vintage Air. And though it sounds full, the expansive, original trunk swallows these necessities with room to spare.
“As a package, this Toronado has it all – classic styling and the new technology of modern automobiles,” Leno said. “What this car really needs is a road trip in Europe to demonstrate what an American GT can really do.”
GM Accessories and GM Performance Parts are sold by Chevrolet, Buick, Pontiac, Cadillac, GMC and HUMMER dealerships. For more information visit www.goodwrench.com.
General Motors (NYSE: GM), the world’s largest vehicle manufacturer, designs, builds, and markets cars and trucks worldwide, and has been the global automotive sales leader since 1931. More information on GM can be found at www.gm.com.
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