praxis

I probably overstepping my bounds since this is my first post but…

Why is it that no one is concerned with the aerodynamics of aero packages? Uh... The “aero” of aero package stands for aerodynamics. One of the factors that drew me to the 350Z was the .29 coefficient of drag and zero lift. (Track model only, however the other models aren’t falling too far behind) I’m sure most of you know that most cars generate lift as the shape of a car is shaped somewhat like a wing right side up. The air has to travel faster over the top of the car then the bottom (flat bottom, rounded top) producing lower air pressure on top then bottom thereby forcing the car upward. This lift increases with speed causing high speed instability as more weight is lifted from the tires producing less traction. (People have actually been killed for this reason) The lift/downforce of a car has everything to do with its corning ability as well for obvious reasons. Even if you were only concerned with acceleration because you’re strictly a quarter miler lift/downforce plays a role as once the car gains speed lift/downforce has a part in the traction of the tires as acceleration continues. Hence the big upside down, downforce producing wings on top fuel dragsters. Often to get this sought after lack of lift/downforce you have to sacrifice drag. This is the case with rear wings. Rear wings will produce downforce but create drag. As an example F1 teams spend huge amounts of money in the development of the aerodynamics in their race cars. (They’re no stranger to the role of aerodynamics in winning races. In fact some officials have stated it plays more of a role than engine power) Some of you may be surprised to know with all that money spent on F1 cars the coefficient of drag is often higher than .40 producing much more drag than our beloved 350z. They sacrifice this drag for the tremendous amounts of downforce the F1 cars produce. They not only eliminate lift but produce the opposite. I can’t remember the exact number but I believe at around 180 mph they can drive upside down on a ceiling because they produce more downforce then the weight of the car (those of you who know, feel free to correct me if I’m off). To further illustrate the trade off between downforce and drag F1 cars have different aerodynamic setups for different tracks. For tracks with larger straight-aways and less corners they have a setup that produces less drag at the expense of less downforce. The opposite is true for tracks with more corners and less high speed areas (straight-aways.)

Once again I’m sure this is not a new concept to most of you, but if you’re interested in going fast drag is also very important. There is perhaps more of an obvious reasoning to low drag then less lift so I’ll spare you people the basic physics talk about drag. I apologize for the above lecture about aerodynamics for the most of you who already know these basic principles. The point being I love the aero characteristics of the Z both having great drag characteristics as well as lift characteristics. To achieve both of these at the same time is a good feat and characteristic of a well designed sports car.

Finally the real point…

Why is it that most aero packages for street cars make no mention of the aerodynamic changes it has to the car. After all isn’t that there purpose? Does that NISMO front lip produce more downforce at the front of the car or reduce drag or both? By how much? Perhaps it creates more down force at the expensive of a little drag. Maybe it’s the opposite. I have no idea because no one mentions it. Not the companies making it or the people on this board. What about the rear wings? What is there downforce to drag ratios? That’s the point of them remember… If they don’t create downforce there are just hunks of material hanging of the rear off you car adding weight and creating drag slowing you down. To be honest I know why companies don’t mention aerodynamics in aero kits. Because they don’t design for aerodynamics. They leave that for the race teams. They design for aesthetic appeal. How it looks will out sell performance characteristics. That’s what people are interested in. When I read the posts in this section of the forum the recipe is the same. Someone posts a pic of a new aero kit and people reply and argue over how it looks. Some people say it’s too “ricy” others love it, etc. etc. Very rarely if ever is there any mention of its aero characteristics. I fear many rear wings generate little if any downforce. I fear many side skirts add drag. And this is all fine and well if you are truly not interested in performance aerodynamics or care more about aesthetics. I’d be lying to say I wasn’t interested how my car looks. But I also care about how it performs. I’d be willing to bet most 350z owners are the same way. Perhaps the solution is to stop calling these aero kits aero kits. Perhaps aesthetic kits or style kits are more suiting. Maybe the term aero kits can refer to the rare and elusive kits that are actually designed for aerodynamics. Of course a little style built into the design certainly wouldn’t hurt true aero kits

I would say that’s my 2 cents, but honestly due to the length of the post it’s probably more change than that. By the way, I really don’t mean any offence to anyone, I just wish there was enough of a demand for aerodynamics that aero makers would actually start designing for this. Yes I know there are places to buy track wings which are actually designed for downforce etc. but wings is the only place I really see this. Front spoilers, side skirts, and rear spoilers are hard to find which actually take aero into account.

praxis

Also happy holidays to my fellow 350z enthusiasts