To test this I first used an irregular shape (water bottle) to test if the dimpled surface would conserve more energy than a smooth one on a non-spherical shape. The bottles were hung and tested on a pendulum structure to ensure air resistance was the major variable.
I found that the dimples did in fact have an impact on the bottle#s energy lost. When doing the multiple swing tests the dimpled bottle lost less height than the smooth, and when doing the one-swing tests to convert energy lost, the bottle had a lower energy lost percentage.
I have concluded that turbulent flow transfers to irregular objects for more efficiency, and therefore would apply to a car.
Science Fair Project done By Teresa H. Netro