Basically, the wing was made up of only the lower element to reduce drag down those very fast Monza straights.
These type of wings were also seen on Italian F3 cars with the only difference being that the
end-plates would be the same as the normal high/meduim downforce setting.
Anyone who has seen the FIA's 1997 year-end review will have noticed it on there
Why was the wing not raced and what were its

