CERV I, II, III, and IV
Written by Bill Bowman
The name CERV stood for Chevrolet Engineering Research Vehicle.
CERV IZora Arkus Duntov as a functional mid-engine, open wheel, single-seat prototype racing car, with Larry Shinoda and Tony Lapine doing the design work. Duntov developed CERV I as a platform for engineers to develop and refine Chevrolet body, chassis and suspension systems. Its impressive performance on the test track drove him to have higher aspirations, the checkered flag at Indy. Due to the AMA (Automobile Manufacturer’s Association) ban on manufacturer-sponsored racing at the time, Duntov drove the CERV I’s demo laps at the U.S. Grand Prix in 1960.
The CERV I was originally equipped with a 283 cid / 350 hp, small block V8 engine, weighing only 350 lbs. Intensive use of aluminum and magnesium engine components saved over 175 lbs. Complementing its lightweight power plant, designer, Larry Shinoda constructed the body structure out of fiberglass, which weighed in at only 80 lbs. The body structure was attached to a rigid 125 lb. Chrome-molybdenum tube constructed frame, welded in a truss-like configuration. Combining these lightweight components helped the CERV I’s 96-inch wheelbase weigh in at 1,600 lbs. The chassis features a four-wheel independent suspension. The front suspension uses independent, variable rate springs with shock absorbers and stabilizer bar. The rear suspension uses independent multilink, variable rate springs, with double acting shock absorbers and the wheels are cast magnesium alloy. Steering is recirculating ball type with 12:1 ratio.
The brake system uses front disc/rear drum, with a two piston master cylinder to eliminate the chance of complete brake failure. Fuel is delivered via two rubber bladder fuel cells (20 gal. total capacity).
Fuel injected small block technology was developed using the CERV I. For even greater performance, Duntov refitted the CERV I with a 377 cu. in. aluminum small block, an advanced Rochester fuel injection system and Indy-style tires and wheels. To match this mechanical updating, Shinoda redesigned its streamlined body structure for greater aerodynamics. Top speed was 206 mph.
Chevy General Manager "Bunkie" Knudsen wanted to get back into racing so the CERV II was planned for the International prototype class with a 4 liter version of the small block. Titanium was used for hubs, connecting rods, valves, and exhaust manifolds bringing the total weight under 1400 lbs.
Construction was started almost at the same time Knudsen was ordered to stay out of racing. The CERV’s II engineering of the drive system and torque converter arrangement was handed over to GM’s engineering team. The result was an advanced 4-wheel drive unit, using two torque converters, a glued together steel and aluminum monocoque, very wide wheels with Firestone, experimental, low profile tires on Kelsey-Hayes magnesium wheels. This was the first time that anyone had designed a variable power delivery to each end of the car, which varied according to vehicle speed. The brakes were mounted outboard. Girling calipers were widened to accept a vented rotor. The car’s first appearance was in March 1964, on the Milford test track. Later that year, GM abandoned the Ford challenge and the program ended.
During development, Jim Hall, Roger Penske, and Bob Clift were among the top drivers who ran the CERV II. Reported performance was 0-60 in 2.5 seconds and over 180mph. As before, the body was by the team of Shinoda and Lapine.
Since the plan to use the CERV II as an anti GT-40 weapon was killed by GM management the car was used as a research tool for a mid-sixties super Corvette that too was cancelled by management. Never raced, the CERV II ended as a show and museum piece.
CERV IIIZR1’s 5.7 liter aluminum block engine. It was twin turbocharged to achieve 650 hp. The engine was mounted sideways in the chassis with a six speed automatic transaxle. The car had 4-wheel drive, with two centrally located bevel gear sets distributing power to the drive shafts. Front to rear torque split was determined by a computer- controlled hydrostatic device that worked in conjunction with the center differential.
The CERV III weighed 3400 lbs. To cut the weight, the backbone was made of carbon fiber. The backbone itself weighed only 38 lbs. Some titanium was used, as well as aluminum castings. The drive shaft to the front wheels was carbon fiber, as were the eight brake rotors, two per wheel. The body was a mix of carbon fiber, Kevlar, Nomex and aluminum honeycomb. The wheels were cast magnesium. The CERV III had active suspension. The purpose of active suspension is to keep the car body flat and level during braking and cornering at the limit of adhesion. Theoretically, once the computer sensed a bump, the car could even lift a wheel and tire over a bump in a road. The car also had computer controlled rear wheel steering, which was used to stabilize a cornering maneuver, compensate for a cross wind or tighten the turning circle at low driving speeds. The braking system used carbon fiber brake pads and rotors. The calipers were inside each rotor. The CERV III had Lamborghini type "scissors" doors. The doorsills held the fuel cell gas tanks with a combined capacity of 23.3 gallons.
The CERV III also had a lot of gadgets inside, including a navigation system and a way of conveying information on all the sub-systems. The wheels were 9.5 x 17-inch front and 11.2 x 17-inch rears. The top speed was estimated at 225 mph.
Once Chevy decided to do a front-engine Corvette, this show car disappeared from the circuit.
The CERV IV was the official name of the test vehicle that the General Motors Corvette group secretly contracted in 1993 to build as a test car for the 1997 Corvette. The Corvette group directed the project, with Chevrolet paying for it. General Motor’s management was not told about it; for fear that they would cancel it.
The Corvette team developed the CERV IV in 90 days in early 1993, got approval to build the car around April of that year and eventually turned the model into the C5, which arrived in 1997. CERV IV was the only CERV designed with a front-mounted engine.