Do the rules still allow ground suckers — active down force promoters — like on the 2J Chaparral?
No on Suckers, however the Front Nose/Wing assembly have multiple layered Wings with End Plates to direct any airflow over the Wing Assembly and down each Side Pods of the Car to the Radiators which is Ducted out the top rear of the Side Pods to flow over the Rear Wing. The Rear Wing has a Slat that opens IF the car is (1) within a Second of the Car in front of it AND in the DRS ZONE (Drag Reduction System) that has 2 spots around the Track that allow it All to work. The DRS FLAP is built into ithe Rear Wing. During the Race when they givesa head on shot You can see it Open and Close.
Sir Chode- Did I get that all Correct ?
no, all active ground effects have been banned for eons