Making fast cars go faster

June 16, 1995
Reeves Callaway has a long history of tinkering and modifying motorized vehicles, trying to wring the most performance and driving excitement from them.

Reeves Callaway has a long history of tinkering and modifying motorized vehicles, trying to wring the most performance and driving excitement from them. It started with a motorized tricycle he built when he was four years old and progressed through college where his senior project for a Fine Arts degree from Amherst College was restoring a Ferrari that had won at LeMans.

He turned all this into a career when he convinced BMW to let him turbocharge its then-new 320i coupe, which he had received in exchange for working as a driving instructor at Bob Bondurant’s driving school. It was nice car, he thought, but it needed another 100 hp. His turbocharger was so successful it evolved into a business providing customers with turbochargers for VWs, Porsches, Audis, and Mercedes-Benzes.

Over the past 18 years, Callaway and his team of engineers have designed and built engines and performance kits for a host of different autos, including Corvettes, Aston Martins, and most recently, Camaros. With all this experience in design, outsourcing, assembly, and marketing, Callaway is now working on his first complete car, the Callaway C7, an ultra-high-performance, ground-effects sports car.


Even more than his considerable engineering skills, leadership is central to Callaway’s success. “I started this business working alone in my garage, and one of the things that teaches you is you can’t do everything yourself,” says Callaway. “It was clear that I needed to assemble a great bunch of people. And what you see today is the result of that early realization.”

What outsiders see is a trio of companies working under the Callaway umbrella: Callaway Advanced Technology (CAT), Old Lyme, Conn., which is responsible for product research, design, development and manufacturing; Callaway Cars, also located in Old Lyme, which, along with CAT, develops automotive products and sells them; and Callaway Competition, based in Leingarten, Germany, the organization’s racing arm. Staffing these companies has not been difficult.

“Fortunately, we’re in the kind of business that attracts clever folks, and everyone wants to work on these kinds of projects: fast, good-looking cars and real engine engineering,” says Callaway. “So our resume file is always overflowing.”

Callaway keeps his companies lean, exploiting short lines of communication and access to some of the best design and manufacturing tools available. His two-building, 18,000 square-foot facility in Old Lyme, for example, houses state-of-the-art CNC machines along with 3D CAD/CAM and FEA, with all the computers linked to the manufacturing line. “Much of our job is to design something very rapidly,” he explains. “All our computers are therefore directly connected to the machines so we can quickly and easily do the CAM side. We don’t have stereolithography yet, but our customers often do. So it can be a good partnership when you join with the right people.”

With all that technology, it’s a job keeping an experienced staff busy. “A capable organization like ours winds up going through projects with great speed,” notes Callaway. “The organization is always hungry, and you have to keep them fed. It’s a constant search for projects that fit.”

One project that was a good fit, and came looking for Callaway, was the Chevrolet Corvette. Impressed with the reliable performance Callaway coaxed out of Alfa Romeo’s 2.5-liter V6, General Motors hired him to do the same for the Corvette. The result, the Twin Turbo Corvette, become a regular production option, and GM sold more than 500 over five years, far more than the 50 or so GM thought it would sell.

Callaway went on to improve the LT1 and LT5-powered Corvettes in 1992, as well as the Camaro and Impala SS. He hopes to do the same to any other car with the LT1, GM’s performance engine of choice. “There’s no question that GM could build the kind of high-performance automobiles we build,” explains Callaway. “But generally, companies don’t go to outsiders because they can’t do the job. More often, it’s because their present staff is already committed, so this is overflow engineering. Besides, the market for these cars is small, and often specialists like us are quicker reacting.”

As a consequence of Callaway’s work with GM, however, other car companies are reluctant to call on him. “Once you get heavily allied with a company like GM, it’s tough to do work with other folks,” he says. “Our association with GM, for example, is a big stumbling block to ever working with Ford or Chrysler. We’d like to make it clear, however, that it shouldn’t be.”

Carving out a niche

Callaway chose to make a living in aftermarket performance products more out of a passion than from any marketing-based studies or research, and even he’s not sure where that passion comes from. “It may be partially genetic, but regardless, we all consider ourselves very lucky to be working in this exciting, highly visible field,” he says.

As for the future of performance cars and their compatibility with EPA regulations, Callaway admits it is not the brightest. “What we do is infinitely promotable, but the market is much smaller than people perceive it to be. And regulations are certainly making it more difficult to turn out new products. But we’re good at finding ways to be compliant and still preserve the excitement.

“Callaway Cars was the first to make high-performance cars comply with strict California rules. That’s one of our criteria; everything we do has to function in today’s society,” he notes. “That’s very difficult and adds to cost and complexity. Few people in the aftermarket industry understand that. A lot of scofflaws are selling products that don’t stand a chance of being compliant.”

Although best known for their automotive creations, Callaway’s engineering team will work on any project where they feel they can benefit the client. As a matter of fact, Callaway regards auto work as some of the most difficult. “It demands almost rocket-science levels of execution at Woolworth prices, and that’s not possible for a specialized organization,” he says. “So we’re always looking for different ways to put our talents to work, and we don’t limit ourselves just to automotive projects.”

Several years ago, for example, CAT designed and built the CNC machinery used by his father’s Callaway Golf company to build golf clubs. “There are some tremendous problems involved in using the kinds of raw materials golf clubs are made of,” explains Callaway. “And it’s not all science. Golf clubs are largely a matter of feel, and capturing the qualities needed to manufacture a golf club, and then making machines that essentially take human error out of the equation was an interesting seven-year process. Those machines are currently making 18,000 clubs per day.”

The C7

Having successfully designed and built engines, drivetrains, bodies, suspensions, and all of the components that go into a car, the next logical step for Callaway and his engineers was to produce an entire automobile. “Since we make high-performance cars, we need to demonstrate our car is competitive with all the other brands,” says Callaway. “That’s why Callaway Competition is in Germany, because we need to show that the C7 can run with anyone. And the best demonstration of reliability, power, and speed is in long-distance endurance racing. That’s why we’re aiming for LeMans.”

After competing at LeMans, C7s will be sold as street cars, and the price, in the $150,000 to $300,000 range, might be considered a bargain. Other competitors in the C7’s class include the McLaren F1 at $1 million, the Jaguar XJ 220 at $700,000, and the Ferrari F40 and new Lamborghini, neither of which even carries a price tag.

“We don’t believe these cars have to be that expensive,” Callaway says. “Good, high-performance cars, especially racers, have an advantage if they are simple, like our C7. When you look at a car like the Bugatti EB110 with its four-wheel drive system, 12 cylinders, and four turbochargers, you know it’s a complex car. We’ve taken the opposite approach. We have a 1,780-pound car with a 560-horsepower engine, and with that power-to-weight
ratio, it must be extremely simple. All
elements of the car are oriented toward

Of all his projects, Callaway considers the C7 his most satisfying. As he says, “It will most embody what we are about.” ■

Sidebar: Callaway’s creations

Over the last 18 years, Callaway Cars has worked on a series of eight different auto projects, with the first started by Reeves Callaway in his garage. Here is a chronological list:

Callaway TurboSystems. Development and manufacture of turbocharger systems for BMW, VW, Porsche, Audi, and Mercedes-Benz.

HH V8 Indy car engine. A completely American-made Indy engine was running as a prototype 11 months after starting the project, demonstrating Callaway’s capability to design and implement a complex, high-performance engine program. The “HH” designation recognizes the contributions of designer Hans Hermann.

Alfa Romeo Twin Turbo GTV-6. Callaway’s success with its TurboSystems led to a formal arrangement with Alfa Romeo to turbocharge its 2.5-l GTV-6 sports coupe. Developed at Alfa’s request to add excitement to its line of cars, the Twin Turbo was a low-volume, high-performance project that gave Callaway experience in meeting manufacturers’ testing, documentation, and production standards.

Callaway Twin Turbo Corvette. Chevrolet, impressed by Callaway’s Alfa Romeo modifications, hired him to do the same with the Corvette. This resulted in the Callaway Corvette, a Chevrolet regular production option (RPO), with more than 500 produced over five years. It was the only time in Chevrolet history a specialist manufacturer was entrusted with a technically advanced, high-performance RPO.

Aston Martin Virage V8 and AMR-1 Group C engine. Callaway re-engineered Aston Martin’s 30-year-old Virage V8 to improve power and meet emissions requirements. The Virage road car was so successful Aston called on Callaway to supply race engines for its 1989 Group C prototype, the AMR-1. It finished 11th in its only appearance at Le Mans.

SuperNatural. When Chevy introduced its LT1 engine in the 1992 Corvette, it effectively ended production of the L98-engine-based Twin Turbo Corvettes. So, Callaway improved the LT1 engine using the principals of tuned natural aspiration and added performance and appearance features to produce the SuperNatural Corvette. Its output is comparable with the Twin Turbo package at less than one-third the cost.

First complete Callaway car. Callaway is building its first complete car, a 1,780-lb, 560-hp, ground-effects sports coupe, to compete at the LeMans 24 hours race.

SuperNatural Camaro. Combining Callaway’s SuperNatural LT-1 engine with other performance and appearance upgrades, this low cost alternative to the Corvette makes Callaway’s engineering available to a wider audience.

Sidebar: THE WEE 8

When NASA’s National Aerospace Plane (NASP) project — the hypersonic, single-stage-to-orbit X-30 — was killed by President Clinton in 1993, he orphaned a wealth of new materials technology. A whole range of high-strength alloys and composites that had been developed to withstand the extreme temperatures the X-30 would experience, from -200° to 1,500°F, would go unused unless they were shown to offer cost and performance advantages over current materials.

To publicize these new materials, a consortium including Brush-Wellman, Howmet, Rockwell International, Texas Instruments Materials Group, and Textron Specialty Materials used some of the remaining NASP funds to design an auto engine. They hoped to interest carmakers, as well as other commercial industries, in using some of the new materials.

The major advantages of the materials are light weight and the ability to withstand high temperatures. “Early estimates showed that an engine made from NASP-derived materials would weigh 50% less than an identical engine made from conventional materials,” says Richard Delagi, project leader for Texas Instruments. “It would also have 50% less rotating and reciprocating mass and could be at least 25% more efficient.”

To design the engine, the group turned to Callaway Advanced Technology (CAT) in Old Lyme, Conn. Engineers there came up with a naturally aspirated 1.5-liter DOHC V8 putting out about 200 hp. Its 16-in.2 footprint and 200-lb weight, led to its “Wee 8” nickname.

“The engine design is fairly conventional. The parts are just smaller and lighter to take advantage of the materials,” says Mike Zoner, chief engineer and managing director of CAT. “Performance gains will be directly attributable to material technology rather than engine architecture.”

“The biggest challenge this engine presents was not in the design,” says Reeves Callaway. “It will come in the execution and fabrication of the new materials. Taking it to production will cost a lot, but it would represent an enormous leap in power density. And imagine what a great motorcycle engine it would make.”

Unfortunately, half the funding was cut during the project, leaving just the design work completed. Supporters are trying to round up the $3 million needed to build the engine and promote the materials.

“I hope the project succeeds and has a life beyond its current function as a demonstrator of the viability of these new materials,” says Callaway. “These materials allow performance gains that can be had no other way, and yet their costs are currently so high no one will use them. But the project should show that if you were to use them in automotive volumes, costs would come down.”


One of the latest projects from Callaway Cars is the SuperNatural Camaro C8, a series of aftermarket packages built for the Chevrolet Camaro. These can be bought and installed individually or in combination, with some boosting power and performance and others purely cosmetic. With all of the Callaway components installed, the C8 Camaro accelerates from 0 to 60 mph in 4.8 sec, has a top speed of 173 mph, and still meets emission requirements in all 50 states.

At the heart of the SuperNatural Camaro is a 383 in3 bored and stroked OHV V8 engine. It features a nitrided crankshaft, Carillo connecting rods, 10.5:1 forged pistons, and cylinder heads ported and matched on a 4-axis LeBlond Makino machining center. The powerplant puts out 404 hp, nearly 50% more than the standard Z28 engine, and 412 lb-ft of torque at 4,500 rpm, an increase of 25% over the stock car.

Two other engine systems, an air intake and an exhaust, can be installed on stock Camaro motors or the SuperNatural 383. The Honker air system uses a molded composite duct and high-flow air filter to increase air flow by 50% over the original air filter. Unlike the original, it takes relatively cool, clean air from outside the engine compartment. Putting the Honker on a stock Camaro adds 16 hp; putting it on the SuperNatural Camaro adds 35 hp, according to Mike Zoner, chief engineer for Callaway.

The Callaway exhaust system consists of tubular stainless steel headers, an intermediate pipe, and a proprietary design, low restriction muffler. Borrowing techniques usually reserved for race cars, Callaway uses stainless steel CNC-machined flanges hand-heliarced to full 1.75-in. primaries made from mandrel bent tubing. This and the Honker yield the biggest horsepower gains without internal engine work, and both are required to get the most out of the SuperNatural 383.

To improve handling and stopping power, a beefed-up suspension adds new trailing arms, strut tower brace, and a tubular lateral link stabilizer to the rear, with stiffer front and rear stabilizer bars to control body lean. A set of high-rate coil springs lowers the center of gravity for better handling, but at the cost of less ground clearance. Koni double adjustable shock absorbers contribute to better handling. Callaway also replaces the 2-piston front brakes with racing-grade 4-piston brakes having an increased swept area and better cooling. The Callaway/Brembo brakes will stop a C8 going 60 mph in 120 ft, and one going 80 mph in 212 ft.

Callaway also provides the CamAerobody, an aerodynamic body package designed by Paul Deutschman, that restyles the exterior and enhances the vehicle’s aerodynamic performance. The new front end, for example, transforms the Camaro from a “bottom breather” into a “front breather.” This reduces lift on the vehicle at high speeds and improves air flow for engine cooling. Down forces on the car and aerodynamic efficiency are further enhanced by the flush, glass-covered headlights and small winglets on either side of the air inlet. Deeper reprofiled side skirts reduce the amount of unwanted air under the vehicle and improve stability, while extractor grills behind the front and rear wheel arches move air quickly through the engine compartment.

Other add-ons include a leather interior and wood veneer accents, a custom shifter, and wider 17-in. wheels with B.F. Goodrich Comp T/A ZR tires.

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