As I said before, all that is, in fact, great theory. However, at street-legal speeds, the actual aerodynaic impact of air dams and spoilers is nill, if not negative due to increased drag.

 

If street speeds are below 30mph, sure. But as any car approaches highway speeds, 60-70mph, aero begins to matter a lot.

You are assuming that these devises create drag...the rather large flap that hangs down just behind the R53's front subframe might at first appear to create drag. In actuality it reduces drag. Don't be so quick to employ your own theory about drag when aero engineers with rather sophisticated equipment know better.

 

It isn't my own theory. It is the theory of an aeronautics engineer, which was actually tested, when I was in college. And, in regard to my drag comment, I was referring to the spoiler.

 

OK then, what do you rocket scientists out there think is the aerodynamic qualities of this combo? BTW: The front splitter is still above the factory front underbody air dam.

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That's exactly why I started this thread. I assumed the thing is for airflow at higher speeds, sounds like that is probably correct. My original question was if you lower the car 2" and you remove it, does the airflow more or less stay like it was originally since the lower edge of the front end is now where the airdam was originally? Maybe we'll never know the answer.

 

What you need to ask yourself is .....Did I pay extra for it? If not you can bet your firstborn that it has a function on the street at legal speeds!

You probably paid extra for that spoiler.....spoilers have no use on the street, they are cosmetic. they do create some drag but thier function is to plant the car to the road in the corners there is absolutely no need except styling for them to be on the street

The AIR DAM that is the discussion of this thread is on nearly every modern car as STANDARD equipment....UNDERNEATH the front end and not pretty and cool. the purpose is to REDUCE drag caused by turbulent airflow beneath the front end and reduce the lift created by the faster moving air over the body.....You do NOT need to be doing 100mph for the air dam to have a function

 

I agree with planeguy.

Articles I have read through the years in auto magazines have indicated that the air dams under the front of modern cars do indeed make a difference in the air flow under the car. And they are effective at normal road speeds. I believe they are primarily there to reduce drag by directing the air to the sides instead of under the car, which helps gas mileage

Rear spoilers on the other hand do not impart any functional benefit at normal road speed. Racing speeds, yes, highway speeds, no. One study I read even said that the spoiler on one car they tested (I think it was the Mustang GT) actually lowered the top end of the car by 5 MPH.

 

Aero aids, as you should know, do not always add down force and therefore do not always increase drag. Many of the aero possibilities considered do not add down force, but make the car more slippery. You referred to these aids as theoretical, and, stated they will increase drag - not always the case, hence my comment about your theory.

My conversations with the F1 fellow and my own personal goals with regard to the mini are not down force related. I am very interested in making this car more slippery - without reducing stability - and there are techniques that will help at highway speeds and at track speeds. The fact that a few of these were removed from the final production vehicle is directly related to style, not function.

 

Thanks meb for your Formula1-advised insight!

I'm starting to become curious as to why LynnEl is so negative regarding this air dam and the fact it's useful in some way. What's the problem Lynn? Do you really think MINI would include something on the "cost-reduced R56" just for grins and a cost-increasing good time? I have no doubts MINI shaved off useful aero tweaks in the name of design aesthetics and cost.....so do you refuse to admit that the air dam is possibly quite valuable?

 

I'm not negative about it. My original point was simply that the OP should be more concerned about it hitting something than any aerodynamic impact. Many features on cars derive from useful purposes, but become more aesthetical than functional on street cars. Many become necesary simply because people expect to see them. I suppose, perhaps, a subconcious factor may be derived from how certain posters pick and chose those items they deride for not being "functional" while fully accepting others. The bottom line is, it's a matter of opinion as to whether a miniscule change in drag or HP is "valuable." For street driving the presence or absence of that 2" stip if not going to be noticed in performance.

 

I'm the OP, and I asked if, at say 80mph (my second post in the thread) if you had indeed lowered the car 2" (same height as the strip) whether the strip still contributed to the airflow/handling the same as it did at the original height of the car. Or whether the fact that the car is now 2" lower makes it more or less obsolete because the bumper is as low as the strip once was. I'm pretty sure that you can only go "so low" and get much of an effect on airflow under the car. I'm getting the picture that nobody really knows the answer to that. It would take some type of airflow testing I think, and I doubt whether that data is available for this particular car. Maybe it's available for similar cars however, but noone seems to know that either, which is really not surprising to me either. But thanks for your responses everyone!

 

I just went and looked at this strip. Two things come to my mind.
1. It is an air dam. The purpose of a dam is to hold things back. In this case it is to reduce the amount of air going under the car. With a smaller gap letting air in at the front of the car and a wider gap letting air out, traveling at high speeds causes there to be a lower air pressure under the car than on top. So, you get some down force. Also, there are fewer air molecules to bump against all the lumpy bits under the car. The underside is not very aerodynamically smooth, so the less air down there the better.

2. The bottom of it seems to be at the same height as the lowest thing that hangs down under the car. This may server as some sort of protection against some materials (snow perhaps). It also may serve as an early warning system when driving very very slowly -- such as when you aren't sure you are going to clear the high center in a dirt road.

As Anne Elk said about the Brontosaurus, "That is my theory, it is mine, and belongs to me and I own it, and what it is too."

 

After reading Robin's post and looking at it for a very long time I changed my mind. I think it's a snowplow.

 

I'm taking my R56 on the track this weekend. I have no plan on removing my air dam.

 

I'm not sure why everyone seems to think an airdam is only for handling, or fuel economy, or looks...

After all, even land yachts in the 1970s sprouted airdams (which could not even be seen given the 4' overhangs) because that's when A/C sales took off, and additional pressure was needed to force air through both the A/C condenser and radiator. By creating a high pressure area in front of the radiator and a low pressure zone behind it, more airflow was made available for cooling. It was probably not for aerodynamics considering the cd was typically 0.49 and the airdam set way back directly under the radiator (which increases lift).

The R56 has an intercooler blocking the airflow there too...

Then there's the reverse mudflap theory: because the overhangs of the MINI are so short, hitting a puddle at speed throws water forward and up onto the windshield destroying forward vision (as well as hydrolocking a number of R53s).