[barnettracing]

Originally Posted by Dave Brand

Downforce is just what it says, a force, so it doesn't have any effect on the mass/weight of the vehicle, so it has no direct effect on acceleration. There will, however, be two factors which will have some effect. Firstly, any aerofoil produces both lift & drag, so the drag component will add to the total drag; secondly, increased tyre loading will increase rolling resistance. Without any data I don't know just how significant these effects will be - negligible, no doubt, at low speeds.

Drag is also a force, hence my reasoning that downforce (which does have an effect on weight, but not mass) would have an effect on acceleration. My physics is a bit rusty and I'm pretty sure that I went horribly wrong in the middle of my reasoning.