[aerohead]

All the low-drag concept cars of the last two decades have active- variable-height suspension to lower the car for highway travel.So your instincts are correct.As other members have touched on,suspension geometry and durability are big issues.------------------------- The low-riders in the past,used hydraulic suspension,with belt-driven pump and slave cylinder rams at each wheel.The front wheels camber would change radically through full range of motion,and I'd never consider that safe for high speed highway travel.----------------------------------------------------------------- After Ford's development of the PROBE series of concept cars,they offered an air suspension on Lincoln cars.The front suspension incorporated a special air strut with linear ball-bearings,which would maintain perfect wheel alignment at all positions.------------------------------------ The front of the car seems to be the challenge for retrofits.Modern supercars feature active suspension.The Bugatti Veyron comes to mind.I'd look at sucessful modern setups and see if they offer clues to technology you can safely borrow.