This fourth-generation Chevrolet Corvette ZR1 is 1 of 25 original “Active Suspension” prototypes. These cars were developed by General Motors in collaboration with Lotus, integrating the hydraulically driven computer-controlled suspension technology of the Lotus Formula 1 Team.
The project cost over $27 million USD and the technology developed was never integrated into Corvette production due to costs – some reports suggest it could increase the MSRP to over $150,000 USD per vehicle.
Quick Facts – “Active Suspension” Chevrolet Corvette ZR1
- The “Active Suspension” ZR-1 Corvette is designed to be the first production car with active suspension in history. The computerized hydraulic system was developed from a similar system used by the Lotus F1 team – GM had purchased Lotus in 1986 and thus gained access to their technology.
- The suspension design uses a high-pressure hydraulic system connected to a Delco computer that makes thousands of calculations every second based on data from sensors that record speed, tire load, steering, throttle and a number of other factors.
- The 3,000 PSI hydraulic system will shift pressure when needed for all but eliminating body roll and reducing oversteer or understeer.
- In the end, the Active Suspension program would never be successfully produced, the technology needed for sensors and other computerized systems could not be mass-produced at an affordable cost at the time.
Active Suspension: How It Works
As complex as it sounds, the basics of the Corvette C4 ZR-1’s Active Suspension system are relatively easy to understand – a series of sensors input data to an onboard computer which then sends precise amounts of hydraulic fluid to the four hydraulic suspension supports, one at a time. wheel.
Above Video: This clip from 1987 provides an overview of the hydraulically driven computer-controlled active suspension system used in the Lotus 99T Formula 1 car. It will be a variation of this developed for the 1990 Corvette ZR-1 – watch till the end to see the Corvette mentioned.
This system allows increased pressure on the outer suspension and decreased pressure on the inner suspension during cornering, helping to reduce or eliminate side-to-side body roll. Similarly, the system can reduce body roll back and forth during braking or acceleration.
The system developed by Lotus and GM engineers for the 1990 Corvette ZR-1 was fully functional and highly effective, the drawback being that it was so expensive that it was not suitable for mass production at the time.
Many of the same GM engineers who worked on this active suspension system went on to develop the Active Handling system that was used from 1996 onwards. By the early 2000s technology had advanced further and GM introduced Magnetic Selective Ride Control on the 2003 Corvette.
Active Suspension Corvette Prototype
In the late 1990s GM made significant profits from its 1986 acquisition of Lotus. Lotus was (and still is) a world leader in vehicle handling and dynamics, and they had developed the LT5 V8 engine for GM – an all-in-one engine. V8 alloy with dual overhead cams per bank and 375 bhp.
While Lotus’ work on the LT5 is well-known among Corvettes, their development of what would be the first active suspension system on a production car for the 1990 ZR-1 is known to fewer people.
Had the system been put into full production, it would have been a major coup for Chevrolet and GM as a whole, beating European exotic supercar makers to their own game. It was clear that GM executives believed in the project – enough to invest more than $27 million dollars and set aside 25 ZR-1 Corvettes for it.
Very few, some say only two, of these original prototypes still exist today, and they are highly sought after by collectors for their historical significance.
1990 Corvette “Active Suspension” Prototype Shown Here
The car you see here is one of the few original prototypes to survive, this is largely due to the fact that it was exhibited for many years at the GM Heritage Museum followed by the Corvette Museum.
Amazingly the car is now for sale on eBay of all places, the owner explaining that it has 12,000+ miles on the odometer almost entirely from its original testing program with GM.
Under the hood (pictured above) you can see some of the hydraulic system and its stripes, and in the car on the center console there is a panel that refers to the Active Suspension system, but it’s not clear if it can be turned on and off.
It’s described as fully functional and it’s up to the new owners whether they drive it, display it, or keep it in a private collection.
The Buy Now price is $89,500 USD and you can click here if you want to read more about it or make an offer to the seller.
Image courtesy of RMC Miami
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Silodrome was founded by Ben in 2010, in the years since the site has grown to become a world leader in the alternative and vintage automotive sector, with millions of readers worldwide and hundreds of thousands of followers on social media.