Aerodynamics of Toyota offered Spoilers

[fnkngrv]

So does anybody have any hard evidence or solid conjecture on which of the Toyota offered spoilers out there for the Yaris sedan which would be the most aerodynamic and not totally form over function?

[CrankyOldMan]

I would have to put them all into the cosmetic category. The whole idea of a rear spoiler is to create downforce on the rear-end proportional to the speed of the vehicle. For RWD/AWD vehicles, this generates more traction on the drive wheels, allowing higher speeds through corners. For FWD vehicles, this would at best reduce oversteer--something that only happens if you have your setup tweaked just right. The other concern--aerodynamics--is usually defeated (spoiled?) by a spoiler, unless it's able to generate a turbulence pattern that reduces drag below the trunk lid. If someone has access to a relatively accurate 3D CAD model of a sedan with and without, I could run some fluid analysis on it.

[fnkngrv]

Might actually remove mine for this upcoming weekend then or else during the week and see what/if any effects are noticed.

[Kaotic Lazagna]

Yeah, almost all spoilers on non performance oriented cars are purely cosmetic and has no or minimal affect on aerodynamics.

[cali yaris]

Any spoiler or wing placed behind the rear wheel, if it produces downforce at all, will produce LIFT at the front of the car - you don't want that.

Focus instead on getting the air underneath the car to speed up. :smile:

I see some canards in your future.

[tooter]

I would have to put them all into the cosmetic category.

I agree...
Legitimate competition cars go fast enough to make them functional, but most all road vehicles don't... especially the pokey little Yaris. :wink:

[xnamerxx]

hatchback spoilers are mainly used for drag reduction rather than downforce. When we were testing the PP cars we removed the giant rear diffuser(not a spoiler but looks similar) to reduce drag on the vehicle and the effect was the venturi's below the car would stall and the car would stop producing downforce.

What you want to do is add a diffuser below the rear wheels and a splitter in front of the front wheels which in turn should create a low pressure zone below the car increasing downforce and reducing aerodynamic drag. Thats why you see lots of diffusers and even mini diffusers on econoboxs and minivans because it can if designed correctly increase fuel economy by reducing drag.

Any car can benefit from reduction in drag and most can benefit from a increase in downforce as long as it reduces lift. Thats why you see lots of the fsae cars with giant wings and diffusers even though they don't reach speeds where there effective.

I've been quite curios about the drag reduction properties of the toyota spoiler as well but I'm willing to bet dollars to doughnuts that they don't do a damn thing and were designed to be tuned out of the airflow.

[fnkngrv]

especially the pokey little Yaris. :wink:

This perception may be misconceived. :thumbsup: Only time will tell. There is nothing pokey about my Yaris :biggrin:

[Kaotic Lazagna]

namer, are you talking about the technical differences between a spoiler and a wing? I think most people just call wings spoilers. lol

[xnamerxx]

hahaha maybe.

[tooter]

This perception may be misconceived. :thumbsup: Only time will tell. There is nothing pokey about my Yaris :biggrin:

Your Yaris earned it's wing.:thumbsup:

[b20vteg]

Yeah, almost all spoilers on non performance oriented cars are purely cosmetic and has no or minimal affect on aerodynamics.

if anything, I would say it actually has a negative impact on performance being that there it's now useless added weight...

[fnkngrv]

guess we will find out this upcoming weekend in my case.

[malibuguy]

New camry hybrid comes with a factory rear diffuser...

[xnamerxx]

New camry hybrid comes with a factory rear diffuser...

My point exactly its all for reducing drag to get better mpg.

[Kaotic Lazagna]

hahaha maybe.

:laugh:

[Jason@SportsCar]

Any spoiler or wing placed behind the rear wheel, if it produces downforce at all, will produce LIFT at the front of the car - you don't want that.

Focus instead on getting the air underneath the car to speed up. :smile:

I see some canards in your future.

Like these ones collecting dust on my desk:

https://lh5.googleusercontent.com/-yG3H__Yk7Lo/T3nUGdG-KBI/AAAAAAAAA2w/DD9c9h0RPu4/s1152/2012-04-02_09-28-50_242.jpg

[fnkngrv]

namer, are you talking about the technical differences between a spoiler and a wing? I think most people just call wings spoilers. lol

That is a common association and misconception. AFAIK when you go to look at valuation of a vehicle it is listed a spoiler as well as when you do the "build your owner" on a manufacturer's site. This is how they are officially listed by the Land Speed staff here which has attempted to bring their rules in alignment with the SCTA and ECTA:

Spoiler
A device on the upper portion of the body for the purpose of spoiling lift.

as opposed to a wing:

Wing:
A special class of aerodynamic effect device intended to provide down force.

I am not an aerodynamic engineer therefore I can't argue or debate the nuances between the two devices. I only know that Toyota calls it a Spoiler as well as NADA, etc when you look it up. I would need to get general direction from Toyota themselves on whether the spoiler that is OEM is specifically and officially merely cosmetic or whether or not their definition is truly as a Spoiler or Wing. The main driving factor for this is that according to an engineering site that I was researching on had this to say about the differences:

Basically, what Bernoulli's principle says, for a physics refresher, is that fluid moving at higher rates of speed create less pressure than fluids moving at slower speeds, and if you have to move an equal amount of air around each side, you can make the distance longer on one side to impart a force. In the case of an airplane, a wing has the longer side of the air foil on top, to create low pressure on top of the wing and high pressure underneath it, which gives the plane enough lift above certain speeds to fly. On a car, you can use a wing the exact same way for the opposite effect. Flip the wing over so that the longer section is on the bottom, then you create a low pressure section on the bottom side of the wing, and a high pressure area on top. This will create downforce on the rear of the car, pushing the rear of the car into the ground. This is more complicated, but ultimately more effective as a wing creates less drag than a spoiler. Basically, all things being equal, if you put a spoiler and a wing on 2 identical cars, set for the same amount of downforce, the wing would have less drag, which results in quicker acceleration and a higher eventual top speed, however minor these numbers might be (as little as .2mph, or as much as 10mph, depending on how aggressive the wing/spoiler are.)

This being said then the lip spoiler that is sold elsewhere in the world would be just that, a spoiler as opposed to what they offer with the S kit and the Thai Vios equivalent which in turn would actually be a wing per Bernoulli's principle since the underside of the device is shorter that the top. This would mean that Toyota's official designation of a "Spoiler" would be wrong by technical definition. This all may be a moot point dependant upon what they would allow me for devices since the car came from production with a Spoiler/Wing.

This is making my head hurt. :bonk:

[fnkngrv]

Like these ones collecting dust on my desk:


These are not allowed on a production category car in this case.

[Kaotic Lazagna]

That is a common association and misconception. AFAIK when you go to look at valuation of a vehicle it is listed a spoiler as well as when you do the "build your owner" on a manufacturer's site. This is how they are officially listed by the Land Speed staff here which has attempted to bring their rules in alignment with the SCTA and ECTA:

Spoiler
A device on the upper portion of the body for the purpose of spoiling lift.

as opposed to a wing:

Wing:
A special class of aerodynamic effect device intended to provide down force.

I am not an aerodynamic engineer therefore I can't argue or debate the nuances between the two devices. I only know that Toyota calls it a Spoiler as well as NADA, etc when you look it up. I would need to get general direction from Toyota themselves on whether the spoiler that is OEM is specifically and officially merely cosmetic or whether or not their definition is truly as a Spoiler or Wing. The main driving factor for this is that according to an engineering site that I was researching on had this to say about the differences:

Basically, what Bernoulli's principle says, for a physics refresher, is that fluid moving at higher rates of speed create less pressure than fluids moving at slower speeds, and if you have to move an equal amount of air around each side, you can make the distance longer on one side to impart a force. In the case of an airplane, a wing has the longer side of the air foil on top, to create low pressure on top of the wing and high pressure underneath it, which gives the plane enough lift above certain speeds to fly. On a car, you can use a wing the exact same way for the opposite effect. Flip the wing over so that the longer section is on the bottom, then you create a low pressure section on the bottom side of the wing, and a high pressure area on top. This will create downforce on the rear of the car, pushing the rear of the car into the ground. This is more complicated, but ultimately more effective as a wing creates less drag than a spoiler. Basically, all things being equal, if you put a spoiler and a wing on 2 identical cars, set for the same amount of downforce, the wing would have less drag, which results in quicker acceleration and a higher eventual top speed, however minor these numbers might be (as little as .2mph, or as much as 10mph, depending on how aggressive the wing/spoiler are.)

This being said then the lip spoiler that is sold elsewhere in the world would be just that, a spoiler as opposed to what they offer with the S kit and the Thai Vios equivalent which in turn would actually be a wing per Bernoulli's principle since the underside of the device is shorter that the top. This would mean that Toyota's official designation of a "Spoiler" would be wrong by technical definition. This all may be a moot point dependant upon what they would allow me for devices since the car came from production with a Spoiler/Wing.

This is making my head hurt. :bonk:

lol, exactly, that's why I just group "wings" with "spoilers." I don't think there are many people who actually distinguish one from the other.

[Kaotic Lazagna]

Since we're talking about spoilers and wings, lol

http://www.youtube.com/watch?v=u6_MUycoPPs

[Jason@SportsCar]

These are not allowed on a production category car in this case.

And that is the very reason they are collecting dust. :laugh:

[fnkngrv]

^ Might be picking a pair or two of those up depending on whether or not I change categories.

[Kaotic Lazagna]

Hey Adrian, are you allowed to tape off any door, hood, and trunk lines (lacking a better term) and fold your side mirrors in?

[Kaotic Lazagna]

And I just looked at pics of your car, what about removing the window visors too? I'm sure they disrupt the airflow (after I wash my car, I can see water droplets on my window going in a circular fashion when I'm driving down the freeway, yes, I don't dry behind the visors).

And if they let you run any rims, how about finding those rims that 39 (Andy) had, I think it was him. They were Work Lead Sled rims, I think. And removing your license plates too? I never took physics, so I'm not sure if any of this would actually help. Just throwing out ideas. lol

[1.5]

Jason what would it take to entice you to brush off the dust and throw those in a parcel?

[Kaotic Lazagna]

These rims

http://www.canibeat.com/wp-content/uploads/2010/09/noel_bb8.jpg

[fnkngrv]

Hey Adrian, are you allowed to tape off any door, hood, and trunk lines (lacking a better term) and fold your side mirrors in?

I do tape off several areas and yes I do fold in my side mirrors.

And I just looked at pics of your car, what about removing the window visors too? I'm sure they disrupt the airflow (after I wash my car, I can see water droplets on my window going in a circular fashion when I'm driving down the freeway, yes, I don't dry behind the visors).

And if they let you run any rims, how about finding those rims that 39 (Andy) had, I think it was him. They were Work Lead Sled rims, I think. And removing your license plates too? I never took physics, so I'm not sure if any of this would actually help. Just throwing out ideas. lol

I have not thought of removing the window visors...that may not be a bad idea...thank you.

These rims

http://www.canibeat.com/wp-content/uploads/2010/09/noel_bb8.jpg

I have moved over to 15s again and the body as well as chasis are thanking me :laugh:. The new combo is lightweight along with the tires each corner is now 31lbs instead of 56lbs. Even though once you have them rolling my 18s weight did not necessarily hinder me, the tire width alone theoretically causes unneeded and unwanted drag. my acceleration is much improved to at least 100mph however I haven't taken the car yet to see if it has netted me much above that yet...keeping that for race days and as a personal surprise. As for other wheel offerings those that you have shown would not be allowed as they are considered a covered wheel since more than 120 degrees of the tread circumference is shielded from the air stream by the covering and outside of what a production vehicle may have come with.


great questions and attempts at assisting! :thumbup:

[fnkngrv]

Jason what would it take to entice you to brush off the dust and throw those in a parcel?

This coming from the guy with an avatar description of "Form>Function"

:laugh:

j/k...couldn't leave that one alone.

[Kaotic Lazagna]

I do tape off several areas and yes I do fold in my side mirrors.

I have not thought of removing the window visors...that may not be a bad idea...thank you.

I have moved over to 15s again and the body as well as chasis are thanking me :laugh:. The new combo is lightweight along with the tires each corner is now 31lbs instead of 56lbs. Even though once you have them rolling my 18s weight did not necessarily hinder me, the tire width alone theoretically causes unneeded and unwanted drag. my acceleration is much improved to at least 100mph however I haven't taken the car yet to see if it has netted me much above that yet...keeping that for race days and as a personal surprise. As for other wheel offerings those that you have shown would not be allowed as they are considered a covered wheel since more than 120 degrees of the tread circumference is shielded from the air stream by the covering and outside of what a production vehicle may have come with.


great questions and attempts at assisting! :thumbup:

Dang, so much for my ideas. hahahaha. hmmm, even the SSR Kreis rims won't work then since they're past 120* covered. So yeah, hopefully taking off the window visors will net you a few mph more.

Another thing, this may sound crazy, but what about doing a full detail (clay bar, polish, and wax) on the entire car (including windows, head/taillights, wiper arms, etc). Anything to decrease drag, right? :wink:

[Kaotic Lazagna]

This coming from the guy with an avatar description of "Form>Function"

:laugh:

j/k...couldn't leave that one alone.

http://www.8thcivic.com/forums/images/smilies/rotfl.gif

[Kaotic Lazagna]

How about the Enkei NT03 rims, not sure if that odd ring will help or be detrimental.

http://www.enkei.com/images/race-series/nt03-large.jpg

[1.5]

This coming from the guy with an avatar description of "Form>Function"

:laugh:

j/k...couldn't leave that one alone.

Yea sorry to disappoint but it will serve only an aesthetic purpose lol

[malibuguy]

Another thing, this may sound crazy, but what about doing a full detail (clay bar, polish, and wax) on the entire car (including windows, head/taillights, wiper arms, etc). Anything to decrease drag, right? :wink:

Hotrod magazine proved that a detail did not make any gains up to 200mph

[Kaotic Lazagna]

Hotrod magazine proved that a detail did not make any gains up to 200mph

Well there you go. :laugh:

I'm all out of ideas on getting a few more mph's outta the car. lol

[david_827]

These rims

http://www.canibeat.com/wp-content/uploads/2010/09/noel_bb8.jpg

What rims are those? They're wicked nice

[cali yaris]

Hotrod magazine proved that a detail did not make any gains up to 200mph

It does, however, make the car feel good about itself.

[fnkngrv]

It does, however, make the car feel good about itself.


+1 and the driver too! No one wants to be on a stage like at a race and have the car look like dog doo

[fnkngrv]

I am actually thinking about changing back to the OEM hood too for this set of runs.

[1.5]

Not trying to call anyone fat I honestly have no idea what you look like groovy lol but you could diet, shed some driver pounds lol

[cali yaris]

OEM hood, no visors, those are good plans.

[cali yaris]

"groovy"... lol, I like that

[fnkngrv]

Not trying to call anyone fat I honestly have no idea what you look like groovy lol but you could diet, shed some driver pounds lol

There is a picture of me with the car on my ABOUT page on my website

http://ttr-online.com

One of the key elements to land speed is knowing that you can actually be either overweight or underweight depending upon the component you are discussing and also over all. Right now weight may/can play a factor in things, but after this year it very well will be rudimentary seeing as how real horsepower and torque will be the equalizer at the higher speeds being attempted. Now I am sure that someone could argue that last statement with me, but in the grand scheme of things I am correct. Primary example is my buddy's Nissan hardbody. The thing is far from aerodynamic yet he is able to reach speeds in excess of 200mph. If anything my car will end up heavier by a couple hundred pounds or more once you add in the safety equipment. Not much else that can be removed from the vehicle in my case therefore the reality is that adding weight will be inevitable. There is a perception that weight is your biggest enemy when in fact, at least with land speed, it isn't the biggest.

Back on topic. It would appear that I have the answers that I was looking for.

[fnkngrv]

"groovy"... lol, I like that

Yeah, I am not sure how that got started...I think that George was the culprit :tongue:

It is Funk N Groove hailing from my DJ days and the fact that I am still pretty informed/into the club/house scene. I have kicked around changing my handle to Tiamat. I know that it can more easily be done across the tracks, but here it appears to be a real eff around for some reason. Being referred to as "groovy" makes me feel like Mike Myers :laugh:

[1.5]

understood, it looks like you weight loss would be minimal and not make much different with everything needing to be added.

[fnkngrv]

understood, it looks like you weight loss would be minimal and not make much different with everything needing to be added.


btw...no hard feelings :biggrin:

You are right in regards to weight of the driver. I would think that if you had a 300lb dude regardless of whether it was obesity or muscle mass that would make a difference compared to a 200lb or 150lb dude for sure especially considering that it would change the aerodynamics depending on how stiff a suspension you have. I have seen some cars on the roads that "sag" quite a lot now that I think about it when there is a hefty person on either side.

[1.5]

exactly I know myself, I could realistically shave 40-50 lbs off myself and thats something that may make a difference.

[Kaotic Lazagna]

So what are the plans to get to 200 mph?

[fnkngrv]

So what are the plans to get to 200 mph?

That is for a different thread and a different day. :thumbsup:

[fnkngrv]

Sooooo....decided to go ahead and pull off the spoiler since it has been determined that it causes more drag if anything. My ass feels so naked now!

http://img.tapatalk.com/a6f8004c-9ece-909a.jpg

http://img.tapatalk.com/a6f8004c-9ef8-581a.jpg


Next year it will have a functional spoiler similar to this and it is street legal:

http://img.tapatalk.com/a6f8004c-a7f6-f700.jpg


OEM hood has been reinstalled as of today and plans for the mirrors are in the works. Also kickin the tires on doing the home depot lip ALM too.

[MUSKOKA800]

My guess is that our OEM spoiler/wing is only cosmetic. In order to function it would increase drag. Toyota wouldn't increase drag significantly as that would also increase fuel consumption which would be counter-productive for the econo-box market.

[Kaotic Lazagna]

OEM hood has been reinstalled as of today and plans for the mirrors are in the works. Also kickin the tires on doing the home depot lip ALM too.

If you're talking about the garage door bottom seal like I have, I suggest not doing it. It'll bend and flap about if you're going that fast, possibly slowing you down. If it's the other HD lip (some solid garden material), then go for it.

[fnkngrv]

If you're talking about the garage door bottom seal like I have, I suggest not doing it. It'll bend and flap about if you're going that fast, possibly slowing you down. If it's the other HD lip (some solid garden material), then go for it.

Didn't end up doing the lip this go around.

[fnkngrv]

My guess is that our OEM spoiler/wing is only cosmetic. In order to function it would increase drag. Toyota wouldn't increase drag significantly as that would also increase fuel consumption which would be counter-productive for the econo-box market.


I can tell you that it makes a difference not having it on for sure after this weekend's event. I am gonna leave it off for a couple tanks of gas as well to see if it impacts my mpg +/-. I would think at this point that it would give me better with out it. I would also be curious of the addition of a spoiler like what is on Jason's truck would improve mph because of the increased aerodynamics especially since you can adjust it with the dampeners.

[Kaotic Lazagna]

I can tell you that it makes a difference not having it on for sure after this weekend's event. I am gonna leave it off for a couple tanks of gas as well to see if it impacts my mpg +/-. I would think at this point that it would give me better with out it. I would also be curious of the addition of a spoiler like what is on Jason's truck would improve mph because of the increased aerodynamics especially since you can adjust it with the dampeners.

Don't forget, my car came without a spoiler. I saw no mpg difference after I added my Thai spoiler. I saw a very minute difference in mpg, like .0x mpg difference when I had my Vortex Generators on and saw the difference in how moisture on my window disappeared with and without it. If you can add those on, I suggest playing around with them (angle and placement wise) using short strings taped at various places and driving down the freeway to get the airflow as stable as possible. I guess try to get the strings all "flowing" down towards the trunk instead of flowing erratically.

[ljming99]

What about underpanels? Im pretty sure that would make some difference