This Guldstrand GS80, serial number 008, was originally built for rock drummer Alex Van Halen and is date stamped as having been completed on August 15, 1988. The car received quite a bit of press coverage when new, thanks to its famous owner, but there is much more to the vehicle than its celebrity parentage. Perhaps most important, it illustrates some of the running changes made to the GS80 series over the years. And, for anyone trying to extract a little extra performance from an L98 C4, the lessons of the past can still be quite instructive.
When Dick Guldstrand introduced the GS80 series in 1986, the car was targeted specifically at Pro-Solo and autocross enthusiasts. He knew all about the needs of these groups, as he was a longtime provider of performance upgrades for the C3 and a direct supporter of a small team of racers from the Western Council of Corvette Clubs. Up to this point, Dick had basically been a tuner. But with the introduction of the GS80, he was venturing into the realm of small-volume manufacturing-tricky territory in both the business and regulatory contexts.
The key element in selling a successful rebadged production car is having enough sales to make the vehicle a legitimate "series built" model. Some changes in the basic pattern can be tolerated, but deviate too much from the engineering concept, and it's possible to lose the economies of scale that result from producing a large quantity of specific parts and assemblies. With only 19 to 25 units built, it is questionable whether the GS80 project ever turned a profit, though a fairly common build pattern may have helped by keeping costs in check. In its day, the Guldstrand makeover cost $15,500 (with iron heads) over the price of a base Corvette.
Effective suspension improvements were critical to the performance of the new C4. Despite being light-years ahead of the C3 design, the C4 had some inherent weaknesses. For example, it was susceptible to even the smallest of variations in suspension calibration. As little as 11/48 degree of camber or 11/432 of toe setting could make a noticeable difference.
Developed and refined over a two-year period, the Guldstrand GS-80 suspension package (hyphen added) proved an effective upgrade. Guldstrand lowered the car by 111/44 inches using longer rear spring bolts and revised spring rates in both the front and rear. The choice for the front was the stiffer Z51 spring, while the rear spring received a lower-than-stock rate.
In most cases, the GS-80 setup used roller-bearing bushings in the control arms. These have less resistance than conventional rubber or polyurethane bushings, resulting in a faster response from the suspension, with less "stiction." These bearings also give zero deflection-just like steel bushings, but without the attendant squeaks and ride harshness.
Poly bushings and Heim-joint end links were used to locate the sway bar, thus allowing it to work more freely. In the rear, all rubber bushings were replaced with Heim joints, and Guldstrand even added his own toe-steer and camber-control kits. Monroe Formula GP shocks were used to dial in the optimum jounce and rebound control. The preferred steering rack was the slower-rate, base-suspension variant.
The end results of Guldstrand's suspension magic were reduced squat and dive along with better camber and toe control. The ride remained comfortable and maintained excellent compliance for street driving.
The engines for the GS80 cars were built by Jim Jones of TRACO, which was just next door to the Guldstrand facility in Culver City (see sidebar). Apart from a few unusual variants, there were three basic stages in the evolution of the powertrain.
The initial engine was based on a seasoned L98 block, which was blueprinted and overbored to 372 cubic inches. The bottom end comprised stock LT-1 pieces. It included a forged crank, "pink" connecting rods, and TRW 9:1 aluminum pistons (later engines used 10:1 pistons). An Engle cam was employed, and a choice of either iron or aluminum heads was offered.
The iron heads were from the L82 engine but used 2.02-inch intake and 1.65-inch exhaust valves. TRACO port-matched and "cc'd" these heads as part of the overall blueprinting process. When the aluminum Corvette heads came into production, TRACO upgraded them by performing a major port job and installing the larger valves from the iron version.
Other changes included intake runners that were siamesed and port-matched to the manifold. TRACO also built its own custom headers, which led to a 211/42-inch exhaust system. The cars were available in both manual and automatic versions, and each one came with an application-specific custom PROM. As a finishing touch, each owner's name was imprinted on the engine-stamp pad.
The first series of powerplants used a hydraulic camshaft. Unfortunately, one of these engines exhibited serious oiling problems while being tested by Road & Track magazine. To prevent similar issues in the future, the second series was modified with a solid-lifter cam and roller rockers. The third version of the engine used similar components but displaced 383 cid.
Horsepower ratings varied over the years (375 seems to be the most commonly cited figure), but in general, the TRACO engines would make power all the way up to 5,500 rpm, much higher than the stocker's 4,000-rpm limit. Peak torque for the iron-head version was 421 lb-ft, while the aluminum-head engines made 430 lb-ft.
The main changes to the interior included the addition of racing seats, a five-point harnesses, a shift light, an oil-temperature gauge, and an analog tachometer mounted on the top of the dash. Seats varied by build period. The Van Halen car now has Prinz seats, but some articles of the time list the original supplier as Konig, and various photographs support this assertion.
The GS80 cars were also fitted with a removable 2-inch rollbar. Although the initial installation took about a week in the shop, once in place, the bar could be removed or replaced in about 10 minutes. This four-point unit is acceptable for most Solo-type events, but the cars had to be fitted with a diagonal support for SCCA competition.
As for the Van Halen car, we know it was purchased in 1988 and that it had the very last of the first-generation engines. When the oiling problems became public knowledge, Van Halen brought the car back for an upgrade. TRACO work orders provided with the vehicle documentation show that this work was completed on February 20, 1989. Despite this attention to detail, the drummer never used the car in the manner it was intended.
The next owner drove and street-raced the car for a couple of years. It was during one of these street-racing exercises that he damaged the car's front end by running into a curb. The top part of the fender and the air dam were replaced, but the damaged wheel was not.
The car was next sold to Chuck Forgey, of Elkhart, Indiana. Chuck bought two new wheels-one replacement and one spare-then proceeded to race the car throughout the Midwest for the next two years. He earned enough trophies to validate Guldstrand's expertise in performance tuning before selling the car to collector Roger Abshire in January 2003.
Roger obtained as much documentation on the car as possible, but a fire in Chuck's house destroyed much of the original paperwork. Fortunately, Chuck had photocopies stored in a separate location. Roger is still negotiating the purchase of the trophies that go with the car, and hopes to eventually incorporate them into the vehicle display in his shop.
TRACO/Travers and Coons
The TRACO engine-building company was founded in 1957 by Jim Travers and Frank Coons. Their work was legend amongst racers, and the shop, located right beside Guldstrand's Culver City facility, was never idle. Notable projects included Roger Penske's '68 Trans-Am Camaro, the Roy Woods Trans-Am AMC Javelin, and Carl Haas' one-of-a-kind "Aircraft Carrier" Lola Can-Am car.
When both men retired in the mid-'80s, the business was purchased by head engine builder Jim Jones. Jim had been hired in 1979 and had helped TRACO stay in the forefront of engine technology. One of Jim's more successful racing programs at that time was with SCCA Showroom Stock Corvette racing, where he helped improve the performance of these production-based automobiles. Consequently, the remainder of the business became devoted to high-end street engines.
Dick Guldstrand relied on Jim to provide the powerplants for all of his GS80 Corvettes. TRACO engines were also installed in some of Boyd Coddington's cars, as well as in vehicles owned by celebrities such as Arnold Schwarzenegger, Nicolas Cage, and Charlie Sheen.
After selling TRACO to Dennis Fisher Engineering in 1996, Jim did a stint with the AJ Foyt team before joining Callaway Cars in late 2000. At Callaway, he oversaw all of the company's engine-development projects, including the 6.8-liter SuperNatural LS6 and the C12-R race motors.
More recently, Jim opened Total Racing Automotive Co. (TRA-CO), in Denver, North Carolina. He still does work for Callaway, currently heading up the company's 600hp twin-turbo C6 engine program.
For more information on Tra-Co,visit www.tra-coracingengines.com.