GHIA IXG CONCEPT
"La Drag-Car da Records"
("The Drag-Car for setting records")
Red with black vinyl interior
Automobiles that upset accepted convention are rare. Henry Ford's Model T did it. So did the 1912 twin-cam Peugeot and the 1964½ Mustang. These landmarks are recognized. What if the landmark employment of undercar aerodynamics by Jim Hall and Colin Chapman was foreseen, developed and employed by Ghia in 1960?
In 1958 Luigi Segre, then head of the independent Ghia design firm, suggested to the University of Michigan that he would take on a promising student for a year's term at Ghia in Turin. The chosen student was Tom Tjaarda, coincidentally (because in 1960 Ghia had no relationship with Ford) the son of John Tjaarda who developed the Briggs concept that became the Lincoln Zephyr.
Tom Tjaarda's first project at Ghia was the Selene. It was followed by the Ghia IXG offered here. Ghia IXG arose from Luigi Segre's enthusiasm for American drag racing, a competition that required dramatically different concepts of form, mass distribution and dynamics, concepts that were in accord with some of the futuristic, even bizarre, flights of fancy then coming from Ghia.
Ghia IXG was created to set drag racing records with a diminutive 948cc Innocenti engine (the Austin-Healey Sprite engine.) To accomplish Segre's objective with the horsepower that could be extracted from the Innocenti/Sprite engine, even tuned by an Italian magician, Ghia IXG had to be both extremely lightweight and aerodynamically efficient. Described by Ghia as "IXG 'The Drag-Car for breaking records'", the Ghia IXG concept's design was extensively wind-tunnel tested and aerodynamically tuned.
Ghia's contemporary description of the concept's wind tunnel development reveals that Tom Tjaarda and his team in 1960 identified and tuned the Ghia IXG's undercar shape for maximum downforce, well before Jim Hall's Chaparral and Colin Chapman's Lotus vehicles made downforce a term of art. It's best simply to quote from Ghia's description:
"The air flow pattern on the top of the car was kept as close as possible to neutral...to minimize drag and lift. Since this is virtually impossible under the car due [to] the Venturi effect between the car and the road, the lowest point was placed under the physical center of gravity. This would be the point of highest aerodynamic lift (in this case sucking down).
"A one-fifth scale model was used to test the principles in a wind tunnel. ...Since the center of gravity has a tendency to shift backwards when a vehicle is in motion, it was found in the test that the negative area under the car was too far back. To stabilize more weight towards the front of the car, the lowest point was shifted forward."
In fact Tom Tjaarda's smoothly-shaped and aerodynamically-efficient form for the Ghia IXG got carried a bit too far. It was built using a space frame, with the composite bodywork bonded to its frame tubes. Tjaarda had left, in his enthusiasm for minimal drag under Ghia IXG concept's gently-sloped lightweight body, and no way to modify its integrated body-frame structure. David Burgess-Wise recounts in his book "Ghia" that when Segre, noted for volcanic bursts of temper, learned Ghia IXG would never be "The Drag-Car for breaking records" he "flew into a tremendous paroxysm of rage; the walls of the plant really shook that day!"
Ghia IXG is offered here as-built. It sits on steel rear wheels, riding on 5.50/5.90-15 CEAT industrial tires some sixty years old. Its physical condition is generally very good although the vinyl covering the bucket seat is torn and cracked. The paint appears to be original; the pattern of the composite bodywork weave still shows through. There is some old paint over cracks, however, suggesting that a thin later coat of paint may have been applied. There is, appropriately, no engine under its lightweight composite engine cover.
How important is this old, and fundamentally flawed, dragster concept? It is perhaps the first concept that identified, acknowledged, measured, quantified, developed and employed undercar aerodynamics to improve performance. Hall and Chapman went on to make racing history by exploiting the principles first tried and tested in the Ghia IXG.