[serialk11r]

Originally Posted by ToyotaObsession

ROFL yes you should. Because you make no sense. Actually he was making sense. Mostly everything.

Yes lift and downforce are the same force applied in different ways, but it's how they are applied which makes them different. Lift is created when you have a Vacuum under something so the atmosphere in an attempt to equalize it rushes in which creates lift. Downforce does the opposite. It's a vacuum on top of an object forcing it down. Vacuum=lower than atmospheric pressure, or negative barometric pressure. You have it mixed up, since a vacuum on top would be pulling the car up.

Reducing lift does not mean creating downforce, it just means reducing the difference in the atmospheric pressure so that's it's more equal. Ideally neutral. You can have 0 lift pressure but that doesn't mean you've suddenly created downforce. So in a strict sense, yes I suppose. If you add a wing to a car, you are counteracting the lift that is already there with the wing. However in effect, reducing lift is the same as creating downforce, it's the same net force on the car.

Since lift is created under the car you can counteract it with a Spoiler, but you won't reduce it. I'm not sure this is entirely true, sure the velocity of air is higher on top of the car so you'll always get a bit of lift like that unless you have some serious bodywork added, but I think you can design a spoiler (at least on some body designs) to change the flow over the top of the car in a way that reduces lift.

Now the less lift you have the easier it is for downforce to work because it has less to work against. Sure, ceteris paribus, if the method of creating downforce doesn't affect what's producing the lift. So a high mounted wing would do that more or less.

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Reducing drag with a spoiler usually ins't very effective. Spoilers will help smooth out the air coming off the rear so that it isn't spilling over and creating a vaccum. But it's not so much reducing drag as it is making it easier for the car to travel though the air. Again, same power, just easier to utilize it. That was a bit self-contradictory. If it helps smooth the air coming off the back, in vague terms, it's probably reducing drag. But most spoilers don't reduce drag, they are there for aesthetics, or to provide desirable aerodynamic characteristics usually at the expense of more drag, but not necessarily so. Spoilers differ from wings in that wings are sorta standalone devices for increasing downforce and spoilers are meant to modify airflow over the body. The only way I can see to interpret "easier ... to travel through the air" is lower drag.

The air coming off a spoiler if everything is working correctly won't interact with the air coming off the bottom because everything is coming off smoothly. In a strict sense, it does interact with the air coming off the bottom but yea it doesn't really do much.

So to summarize, increasing downforce isn't reducing lift. It's simply bullying lift to have less of an effect lol.So not really, there are a lot of ways to produce downforce, and any reduction in lift is an increase in net downforce. I don't know if you read my previous response, but a diffuser decreases pressure below the car, producing a downward force. Now since the top of the car can still have a lower net force, you might say the diffuser is just reducing lift. But it doesn't really matter, downforce, lift, they're just forces. Anything changing the net force (due to air) does just that, it changes the net force.

responses in bold...and if you missed my previous post, I explained why a diffuser can cut drag.
oops you guys posted while I was typing that. well it still applies.