No argument here that Ghias at at their most beautiful au natural.
The wing is experimental and not used for historic racing. It's purpose is to provide enough room for a turbo and intercooler. In the view above, a non-turbo engine is in place.
We do run a small RSR style "duck tail" in HSR as the above photo shows.
Here is a classic Ghia beauty shot, even dressed for competition.
Turbo and intercooler should be easy in a ghia engine compartment. You have tons of room in there compared to a bug. Even with a decklid it should be very doable.
That big whale tail wing on the 930's covers the water intercooler. You can sprint with a non-intercooled system or act as a daily driver, but for endurance racing, you need either a big air-to-air intercooler or a only slightly smaller water intercooler.
Our trouble is the Ghia has good width in the engine compartment, but like the 911, no height.
The experimental "turbo wing" wing allows us to move the intercooler just aft of the engine, a la 930.
We'll never run the "turbo-wing" on the HSR Ghia unless as a joke for intimidation purposes to spook the 911's and E-Jags in our class. It might be used on a LeMons Ghia.