Steve-
the FF bodywork (ie: aero) rules have been an embarassment for years; none of the terms are defined and the tortured language that attempts to define "flat" is ambigous best-on-best! in the absense of objectively verifiable rules, the rules mean whatever the "Big Dog" in Topeka threatens people with. see Fastrack posted February 20, 2008 keeping in mind a complete "rewrite and reorganization for clarity" of the FF engine rules is also included (full of new rules masquading as anything but).
It is the intent of these rules to minimize the use of “ground effects” to achieve aerodynamic downforce on the vehicle. Thus, for thefull width of the body between the front and rear axles, the lower surface (surface licked by the airstream) shall not exceed 2.54cm (1 inch) deviation from the horizontal in any longitudinal section through that surface. (This is not to be interpreted as requiring a floor pan beneath the motor, transaxle, transmission, or final drive housing.) Diffuser undertrays or venturi tunnels are prohibited. No aerodynamic devices (e.g., skirts, body sides, etc.) may extend more than 1cm (0.394 inches) below the lower surface of the floor pan to the rear of the front axle. Seat buckets or other protrusions shall not circumvent this rule. It is not permitted to duct air through any part of the bodywork for the purpose of providing aerodynamic downforce on the car. All ducted air for heat exchangers (water/oil) shall pass through those heat exchangers
as written, the rule says "flat" within 2.54cm (ie: 1") of the local horizontal
(diviation has NO direction constraint) between the front and rear axles with
no flatness restrictions in front of the front axle line and behind the rear axle
line. the "Big Dog" now says diviations are only "up" apparantly meaning the
equivalent of plus or minus 1.27cm from local horizontal or plus 0.00cm minus
2.54cm from local horizontal. then there's the sticky problem of how, when,
and where to make measurements to confirm compliance with the rule......
as written, I'm good with 3.08cm of total curvature up at any angle with respect
to the direction of travel (assuming a Zero Tolerance approach to compliance
verification). since I have no idea what any of the undefined terms mean AND
I know your heart is devoid of any of the prohibited "intent", you'd be good to
go!!
without objectively verifiable definitions of all of the terms in the rules as written,
the conversation will always be circular and in my opinion devoid of any value
except humor.
Art
artesmith@earthlink.net