Tom2

Obviously, you don't know me very well at all. I do know it all.

If you don't like it, tough shit.
:sqntfawk:

tmk70

I know you enough to know that I don't want to know you, pal. Just keep your fuckhead comments to yourself, that's all.

Tom2

I have a better idea, dickboy....

Instead of telling me what NOT to say, how about YOU just don't read it, tough guy.....

tmk70

Reading your posts makes me realize that true and pure assholes really do exist. I think I speak for a few people here at A-CL when I say VERY few people view you as the voice of reason...or the voice of anything, for that matter.

Tom2

Good. Continue to read my posts then....

.... But stop crying like a little bitch already.....

synth19

hahahhahahah LOL LOL
(sorry tmk, I do agree with you, but that was just too funny)

Dom418

If anyone took that seriously, wouldn't the proper question how the hell did you get you car up to 180-190???!!!!

tankmonkey

1. I'm not contradicting my statements, I'm gainsaying your position. to wit:

(tankmonkey): properly designed wings require structural support to transmit the downforce to the chassis.

(tom2): but the 911 doesn't have these structural supports, so you must be wrong.

(tankmonkey): no, the 911 has a spoiler, not a wing, and therefore wouldn't need such bracing.

2. the spoiler on the 911 may indeed be creating a small amount of downforce (20 lbs represents 1/2 of 1 percent of the curb weight of a 911 turbo - hardly significant) but that is merely a fortuitous extension of the spoiler's real benefit: reduction of lift.

think about it: why would anyone brag about making an insignificant amount of downforce? because it is an indication of the effectiveness of the spoiler (i.e., it's so effective at eradicating lift that it actually produces a small amount of "negative lift" in the process).

I think the term for bragging about things like this is "marketing."

3. I've never implied that spoilers and wings are mutually exclusive. one design is inherent in the other (a wing will still create drag even if its angle of attack is set to zero), but the functions they perform are distinct.

4. as noted above, the current model 911 turbo weighs 3395 lbs. the downforce generated by the spoiler is (according to your sources) 20 lbs. this represents 1/2 of 1 percent (.5%) of the car's curb weight. insignificant.

but for the lift reduction charateristics of the spoiler, you'd almost be just as well off by removing the appendage entirely and replacing it with a 20 lb bag of dog food on the parcel shelf behind the driver. (disclaimer for tom2: I'm being facetious, of course, knowing that the extra weight would have to be carried around all the time, the extra weight would affect braking and handling at all speeds, and the weight of the spoiler itself would need to be factored in. )

5. this thread started over the cl's spoiler, our debate started as a result of your blanket statement "A rear spoiler on a front wheel drive car is just retarded." strictly speaking, that statement was false, because even front drive cars can benefit from a reduction in lift at speed.

6. like I said: body lift at the rear = less weight over the rear (which is NEVER good at high speeds on any drive configuration car)

7. I stand by my position that your original statement regarding spoilers on fwd cars is retarded.

bobm

I have the factory spoiler. My way of thinking is that if you have
a RWD car, then the spolier will help hold down the rear.
Our cars are FWD......... it would make more sense to have a front
air dam then a rear spoiler.
any one agree?????

fender4

JESUS; time for a group hug here. Also, I don't have a rear spoiler.

acuraboy_RENAMED

i spoiled mt rear...but my front is still ok

Tom2

tankmonkey,

I'm done debating this issue with you.....

1. You ARE contradicting your own statements. If you read this thread again, you just might realize it.

2. For you to claim that ANY amount of downforce is insignificant is just silly. To compare the amount of downforce with the curb weight of the entire car is even more ridiculous. If you were travelling in a 3400 lb car at 190 mph and the rear began to get loose due to lifting, wouldn't that 20 lbs of downforce be significant? It just might be enough to save your life.

3. Our debate may have started over my original statement (in your mind, not mine), but there really wasn't a debate until I read your thread which stated, "spoilers generate drag, not downforce". That was the statement that sparked this debate (in my mind). Why can't you admit you were wrong for saying that?

4. A rear spoiler on a front wheel drive vehicle is retarded

tankmonkey

wuss.

(seriously, though, I think we've managed to beat this one to death...)
well, I'm certainly contradicting *your* statements.
nice nonsequitur, btw...

so if a 3400 lb car traveling at 190 mph makes a net 20 lbs of downforce, how much lift is it experiencing? (hint - you're looking for a negative number here...)

anyway, I guess if I *did* think that a 20 lb difference was going to be critical at 190mph, I'd make sure I topped my gas tank off beforehand...
because I'm not wrong?

spoiler (noun) -[list=a][*]a long, narrow hinged plate on the upper surface of an airplane wing that reduces lift and increases drag when raised. [*]an air deflector usually mounted at the rear of an automobile to reduce lift at high speeds. [/list=a]
source: the american heritage dictionary of the english language, 4th ed.


d'oh! :P

Tom2

tankmonkey

nice catch.

feel better now?

btw, you omitted the 'r' in 'your' while typing this sentence in an earlier post:

tmk70

Tom2

Feel better? LOL, I felt fine all along. I told you that I wasn't going to debate the spoiler/wing thing anymore, that's all.

Funny that you should compare an ovbious typo to an even more obvious mistake

Anyway, wing or spoiler? You be the judge:

Tom2

Better yet..... wing or spoiler?

fender4

Good photo of the f16. I am a engineer for new components on the new strike fighter; we also make the f16 in my factory. This guy must work here somewhere.

tankmonkey

beauty.


<hr></hr>

I'm particularly fond of this biplane jobber with the side extensions... :sqnteek:




<hr></hr>

the suspension is sagging from all the extra "downforce" provided by this one...

(5 bonus points if you can find the st. louis arch in this picture...)

kastegir

Wow, someone that's been around as long as me... color me impressed.

codehead

Doh! jrock, now yer pissing me off!

Hey, surface area is surface area. You can't get negative surface area. Mold a lump of clay into a different shape with the same surface area, and you get different drag, potentially.

Anyway, don't bug me about the wing. Go nag Infiniti about why they say drag is 0.01 less with the wing. I could point to some references on the web to back up what I said about turbulence and all. The point was that adding surface area can (not does) reduce drag. Just a point of physics. I don't have a wing, and don't suspect that it doesn't impact a CL-S in any positive way other than aesthetically, if you like 'em.

EricL

The whole issue of adding or removing area oversimplifies fluid-dynamics. It is certainly possible to add area to reduce turbulent flow, and decrease the induced drag that can result from certain types of rear-end designs. Normally, the drag on a wing is related to its lift (in the case of an aircraft), or its downforce (in the case of most car's aero devices). However, there are occasions, where a wing or "more area" is placed next to wheels, the back of the car, and so on, and the drag is reduced.

There really is no "simple" answer -- it is a matter of going to a wind-tunnel and actualy measuring the drag on the car.

So, maybe yes, maybe no -- it depends...

Finally, if someone wants to "visit" this subject, there are probably some diagrams that will clear up some confusion about frontal area vs. streamlining that happens in back of a shape:




Links and excerpts

http://wings.avkids.com/Book/Sports/...acecar-01.html

"The rear spoiler can reduce flow separation at the rear window, which reduces drag. It also increases air flow under the body, which promotes downforce at the rear of the car..."


(The if it helps depends on the how much flow divergence/flow separation there is and that is influenced by a number of factors including how steep the rear window is. For example, it would be "lousy" in a "hatchback"...)


AND


"In the early 60's, Ferrari's engineers discovered that by adding an air foil ( we simply call "Wing" ) to the rear end, lift can be dramatically reduce or even generates net downforce. At the same time, drag is only slightly increased...."

(They are talking about a Ferrari, and that is a nice blended shape [towards the rear]...)

http://home.planet.nl/~imps/tech/aero/tech_aero.htm