Gonna say that stumbling into this video, and your channel in general is amazing! Thank you so much for making these vids! Great to get some more understanding of the aero side of racing!
Really interesting, I'm thinking of buying an SUV and the car dealership recommended a Spoiler and I was thinking Um Omg what for? Its an SUV not a freakin race car but the things you mentioned was what they were trying to promote in the way of Accessories. Your vids bring greater understanding for Women like me who, dont know much or anything about Aero Dynamics. Thank you! 👍🏼🙃🤔🤨
I've been watching your automotive aerodynamics videos and loving the hell out of them. I've learned so much listening to you and watching all of the details in the videos. I watched the Civic one (sorry for my late comment) and i remember one curious thing about a car.... how about the Porsche 928? It's been said that it's more aerodynamic going backwards than forwards. Is it possible for you to get a plastic or a die cast model of that? I think Mythbusters made an episode about it. And also , there's a 928 S4 and 928 GTS both with a rear wing. You can test with and without the wing. I think that would be cool to see and i know a lot of people would want to see that. Also i would like to see some test about the aerodynamics in Nascar , V8 Superstars , Le Mans , F1 and other forms of racing or even with regular road cars (i mean two cars racing together , one glued to the back of the other, how's that affect the aerodynamics? 1 car vs 2 cars) and driving behing trucks. Keep doing that awesome work that you've been doing and i'll keep watching you. Greetings from Portugal mate! ;)
This is such an awesome series! I'd love to see one on the impact of flat vs. OE open underbodies, if that can be seen on small models. One on hatchbacks with more upright rears than the Civic (e.g. Mk4 GTIs) would be great also.
GasInMyVeins20AE I would like something similar. My daily is a 2003 Pontiac Vibe GT with a more upright rear window, as well. Mine is spoilerless but it was offered with a dual one quite like the Civic in the last vid. It would pretty easy to install a gurney flap for the hell of it on the rear top but I'm curious how much it would help, if at all.
@@RotaryRebuilder uNABLE TO FIND YOUR VIDEOS ON THE EFFECTS OF REAR BOTTOM DIFFUSERS. .. LOVE YOUR VIDEOS .. wISH YOU COULD DO THE 2020 aSTON MARTIN VANTAGE .... MOST ALLVIDEOS MENTION THAT THE REAR IS UNSTABLE ON TURNS.
Interesting, didn't know a Gurney Flap was effectiver on a spoiler. I run a 10in Spoiler for autocross, top speed is irrelevant to me. downforce at 40-50mph is king here. will be adding a Gurney Flap forsure.
making holes to the rear bumper (as high as possible) will reduce the wake size? in my case (VW bug) holes below the tail lights, and in the rear apron will be helpful? I think also a big drag area is behind the front wheel fenders, scape holes there could help? thanks for your comments Great video!
you can do a video on sedan/wagon , i love the wagons and i thing that maybe the wagon is a little bit aerodinamic than the sedan good loock from argentina!
keep making these videos i really enjoy it! could you possibly go into equations etc a bit more? being mech eng im aware of this sort of stuff but would like to see explained how they tie into what im seeing visually in terms of the air streams. thanks very much and keep it up!
Robert. I'm trying to keep it simple so that general audiences can understand (also the videos are already very long), but if you would like more info. You can always email me!
Like your videos but you seem to forget to mention, that big downforce in the rear results in bigger lift at the front. You have to compensate that with additional lip/splitter modifications. By just adding a huge wing/gurney in the back you dont get full grip potential of a car.
Hello Graham, I just recently stumbled on your channel from a thread in FT86Club and I really enjoy your work. Keep up the great work! I have a question for you regarding a wing I have installed on my FR-S. I have a Rocket Bunny V2 wing installed on my car. I love the way it looks aesthetically, but I would like to know whether it produces downforce or drag. Thanks for your time and I look forward to all your upcoming videos!
Great video as always. If this is how rear downforce is generated, how can front-downforce be generated? I'm curious to see how a slight gurney flap and front lip splitter would aid on a newer hatchback body style. 90% of my interest is cosmetic, but I am hoping it will not destroy driveability, or increase drag too much. Thanks
I have a 1987 Mitsubishi Lancer SL. I know the box shape is a challenge aerodynamically. Can you suggest any modifications to get more rear downforce and/or make it more slippery?
If you added vortex generators to the rear roof to help keep the flow attached would that not make the spoiler more effective? And those wakes smaller too
I think he was saying that the VB, VC, VH and VK all had pretty ordinary CD figures but the only data he had was for the VL. He then compared it to a later model, VN? Where they had improved the aerodynamic efficiency.
Awesome tutorial and video. I'm now a subscriber. I'm currently making some aero bits for my Alfa 4c. Specifically wondering if adding a gurney flap to the stock spoiler would be helpful in terms of reducing lift? If so how tall and at what angle to the spoiler? Any help or advice would be hugely appreciated.
Another excellent video. Did you consider the effects the flat bottom model has on the flow structures? If so, how much do you think it changed the flow behind the car?
What is the effect of vehicle rake on the airflow? Or even the effect of hard turns where one side dips heavily into turns and the aerodynamics are upset?
Hi brother, have you ever studied a old Porsche 914? These thing have a weird shape and as much as I try and brain it ,I still don’t know why they made it this shape.
At 31:00 you say that changing (increasing) the y momentum upwards, we can produce more downforce is that correct? Doesn't increasing the velocity upward result in decrease in the pressure at rearend which inturn produces lift. Please elobrate me. Thanks
can you do an integra dc5 without spoiler, type r spoiler and maybe aftermarket spoiler? also would it be beneficial on a front wheel drive car on a track with a long straight?
Wanna help a novice design and develop one off aero for a garage build for a car very few people remember or even know of anymore? 2800lbs and 400+whp, front wheel drive for hill climb and autocross. I have been watching these trying to remember my physics from college, and looking at ways to design and test a scaled model to test theories.
I really want to reduce drag on my Sidekick 95'. Let me know if u feel up to it
9 лет назад+1
great video! Hope it'll be useful for the guy who asked you! I have a question unrelated to the video, lately I've been trying to save fuel, and to do so I stay 10/15m from trucks going at 90km/h on the highway, to benefit from the drafting effect of it. I don't want to go any closer to it because it would be dangerous if the truck happens to brake suddenly, but I was wondering if it really made a difference at that distance. My car tells me I drop from 5.5L/100km to 2.9L/100km when I do it, but I don't know if it's really accurate. (maybe it's just a coincidence because other conditions were changing when I tried ) To be short, I'd like to know how close to a moving truck should you be to really benefit from the drafting effect ? ( Not saying I'm going to do it if the answer is "2 meters", I don't want to drive dangerously. ) Anyway, even if you never answer that question, keep up the good work, I'm really enjoying your vids! Cheers from France!
Guss, You most likely need to be within the main wake of the truck to see the most benefit. My guess is that the length of the main wake is on the order of the width of the truck. So probably 3-4 meters. I wouldn't recommend driving this close.
I have tested this drafting method some time ago and i found that it depends on the shape and speed and your distance to the front truck, if its a big long container that moves fast and you run closely behind it youd get considerable cut in fuel consumption and you would immediately feel it by reducing push to the gas pedal by half to maintain your speed (specially for less aero sedanes like mine) and at the close distance youd easily feel the turbulance and unsteadyness of the stream behind the truck by a huge baffeling , a little more distance the stream become more stable, and if you increase your distance further more at a specific distance if you take down side widows you can feel the powerfull downwash vortex trailing the truck, farther from this point the drafting would be minimal
If there's any sense in the way your car's trip computer works this number out, then it'd take momentary fuel flow and speed, do some maths with it and spit out a number. At that very moment, it really is consuming that little fuel. The reason for this could well be sitting inside a lorry's wake, however it could just as easily be a gradient change, so I'd suggest repeating the experiment in more controlled conditions. In my opinion though it's a veeeeeery bad idea. Motorways are boring. As you relax and settle into a long drive (especially sitting behind a lorry!) your reaction time doubles (or worse) and leaving yourself less than 1 second to react to whatever it is that's going on is not the way to go. Burn the extra fuel, stay safe!
Won't the gurney flap just on the rear cause a imbalance between the front and rear down force causing the car to push? Or is his car already loose in that turn?
Hello Sir Grays Garage! Adding a rear spoiler to a C7 Corvette 1LT is a good thing over all? Will it strain the engine, slow it up in a bad way or, etc.? And some important pros or cons? And overall install rear spoiler or not? Thanks! Here is link to C7 without spoiler and wondering if good to add rear spoiler to it? www.autoguide.com/new-cars/2017/chevrolet/corvette/1lt/2dr-stingray-cpe/
Your model doesn't reflect real life. Air flow over the roof of the VH travels diagonally over the rear of the roof not just parallel, and around the rear windows and is acting in 3 dimensions not just 2. The problem with the VH (& VB to VL's) is they produce a lot of lift in standard form and get very floaty over 120km/h. In the rain at high speed you can see water drops going up the side windows from the low pressure over the roof. So your starting with a handicap before you add any aero improvements.
have you done an episode on roof spoilers on sedans, www.vparts.se/media/catalog/product/cache/3/image/400x/9df78eab33525d08d6e5fb8d27136e95/i/m/image_44722.jpg like this, and the effects of them, if not i would be interested in seeing an episode on them
Gonna say that stumbling into this video, and your channel in general is amazing! Thank you so much for making these vids! Great to get some more understanding of the aero side of racing!
Really interesting, I'm thinking of buying an SUV and the car dealership recommended a Spoiler and I was thinking
Um Omg what for? Its an SUV not a freakin race car but the things you mentioned was what they were trying to
promote in the way of Accessories. Your vids bring greater understanding for Women like me who, dont know
much or anything about Aero Dynamics. Thank you! 👍🏼🙃🤔🤨
You really need to do more videos. I love this channel.
I've been watching your automotive aerodynamics videos and loving the hell out of them. I've learned so much listening to you and watching all of the details in the videos.
I watched the Civic one (sorry for my late comment) and i remember one curious thing about a car.... how about the Porsche 928? It's been said that it's more aerodynamic going backwards than forwards. Is it possible for you to get a plastic or a die cast model of that? I think Mythbusters made an episode about it.
And also , there's a 928 S4 and 928 GTS both with a rear wing. You can test with and without the wing.
I think that would be cool to see and i know a lot of people would want to see that.
Also i would like to see some test about the aerodynamics in Nascar , V8 Superstars , Le Mans , F1 and other forms of racing or even with regular road cars (i mean two cars racing together , one glued to the back of the other, how's that affect the aerodynamics? 1 car vs 2 cars) and driving behing trucks.
Keep doing that awesome work that you've been doing and i'll keep watching you.
Greetings from Portugal mate! ;)
I feel like I'm going back to school... but it's sunday, I drink a beer and we talk about cars! Let's drink and learn! I like that!
This is such an awesome series! I'd love to see one on the impact of flat vs. OE open underbodies, if that can be seen on small models. One on hatchbacks with more upright rears than the Civic (e.g. Mk4 GTIs) would be great also.
I'll keep my eyes open for a Mk4 GTI, stayed tuned!
GasInMyVeins20AE I would like something similar. My daily is a 2003 Pontiac Vibe GT with a more upright rear window, as well. Mine is spoilerless but it was offered with a dual one quite like the Civic in the last vid. It would pretty easy to install a gurney flap for the hell of it on the rear top but I'm curious how much it would help, if at all.
GraysGarage how about a Chevy sonic?
@@RotaryRebuilder uNABLE TO FIND YOUR VIDEOS ON THE EFFECTS OF REAR BOTTOM DIFFUSERS. .. LOVE YOUR VIDEOS .. wISH YOU COULD DO THE 2020 aSTON MARTIN VANTAGE .... MOST ALLVIDEOS MENTION THAT THE REAR IS UNSTABLE ON TURNS.
You should probably look into studying how open windows affects airflow and drag,
Brilliant! thanks for sharing knoledge
Interesting, didn't know a Gurney Flap was effectiver on a spoiler.
I run a 10in Spoiler for autocross, top speed is irrelevant to me.
downforce at 40-50mph is king here.
will be adding a Gurney Flap forsure.
Just amazing... i do like ur videos so much cuz u go deep on xplanations... thanks a lot for clear ma mind. i respect ur work- 💪
People. If you don't mind the physics, just chill-out to the background music.
Thanks great video once again!
making holes to the rear bumper (as high as possible) will reduce the wake size?
in my case (VW bug) holes below the tail lights, and in the rear apron will be helpful?
I think also a big drag area is behind the front wheel fenders, scape holes there could help?
thanks for your comments
Great video!
you can do a video on
sedan/wagon , i love the wagons and i thing that maybe the wagon is a little bit aerodinamic than the sedan
good loock from argentina!
awesome video man
Walkinshaw also made a Limousine VL
keep making these videos i really enjoy it! could you possibly go into equations etc a bit more? being mech eng im aware of this sort of stuff but would like to see explained how they tie into what im seeing visually in terms of the air streams. thanks very much and keep it up!
Robert. I'm trying to keep it simple so that general audiences can understand (also the videos are already very long), but if you would like more info. You can always email me!
Robert Lunn Actually finished watching the video :/. sorry shouldnt have commented so quickly. keep it up i hope you continue producing these
Like your videos but you seem to forget to mention, that big downforce in the rear results in bigger lift at the front. You have to compensate that with additional lip/splitter modifications. By just adding a huge wing/gurney in the back you dont get full grip potential of a car.
Hello Graham, I just recently stumbled on your channel from a thread in FT86Club and I really enjoy your work. Keep up the great work! I have a question for you regarding a wing I have installed on my FR-S. I have a Rocket Bunny V2 wing installed on my car. I love the way it looks aesthetically, but I would like to know whether it produces downforce or drag. Thanks for your time and I look forward to all your upcoming videos!
Great video as always. If this is how rear downforce is generated, how can front-downforce be generated? I'm curious to see how a slight gurney flap and front lip splitter would aid on a newer hatchback body style. 90% of my interest is cosmetic, but I am hoping it will not destroy driveability, or increase drag too much.
Thanks
Van you explain aerodynamics of pickups?
Could you helped with my champcar endurance race car. It's a 1986 mustang. Basic set ups . Wing or spoilers.
thanks, this is great. subscribed. i was going to email you but the website appears to be defunct...
I have a 1987 Mitsubishi Lancer SL. I know the box shape is a challenge aerodynamically. Can you suggest any modifications to get more rear downforce and/or make it more slippery?
I added a gurney flap on my hood vent.
If you added vortex generators to the rear roof to help keep the flow attached would that not make the spoiler more effective? And those wakes smaller too
F J also interested in seeing a video adding the roof vortex generator to see what the effects are on the wing with the gurney flap.
Nice Video! What about an additional roof spoiler for the Holden?
Can you do one on DC5 type R wing in comparison to the Dc5 type S duck tail, then when a type S add on a eBay GT style wing
im building a dc5 type r for track and dont know if i should buy an aftermarket spoiler. it would really help
There actually was the VK before the VL 1984-1986.
I think he was saying that the VB, VC, VH and VK all had pretty ordinary CD figures but the only data he had was for the VL. He then compared it to a later model, VN? Where they had improved the aerodynamic efficiency.
Awesome tutorial and video. I'm now a subscriber. I'm currently making some aero bits for my Alfa 4c. Specifically wondering if adding a gurney flap to the stock spoiler would be helpful in terms of reducing lift? If so how tall and at what angle to the spoiler? Any help or advice would be hugely appreciated.
Another excellent video. Did you consider the effects the flat bottom model has on the flow structures? If so, how much do you think it changed the flow behind the car?
What is the effect of vehicle rake on the airflow? Or even the effect of hard turns where one side dips heavily into turns and the aerodynamics are upset?
Hi brother, have you ever studied a old Porsche 914? These thing have a weird shape and as much as I try and brain it ,I still don’t know why they made it this shape.
At 31:00 you say that changing (increasing) the y momentum upwards, we can produce more downforce is that correct?
Doesn't increasing the velocity upward result in decrease in the pressure at rearend which inturn produces lift.
Please elobrate me. Thanks
can you do an integra dc5 without spoiler, type r spoiler and maybe aftermarket spoiler? also would it be beneficial on a front wheel drive car on a track with a long straight?
So how about systems that increase down-force but no additional drag like ground effect techniques, or do they still produce down-force?
Why do call vortices bubbles?
could you look at formula 1 cars and diffusers?
Wanna help a novice design and develop one off aero for a garage build for a car very few people remember or even know of anymore? 2800lbs and 400+whp, front wheel drive for hill climb and autocross. I have been watching these trying to remember my physics from college, and looking at ways to design and test a scaled model to test theories.
I really want to reduce drag on my Sidekick 95'. Let me know if u feel up to it
great video! Hope it'll be useful for the guy who asked you!
I have a question unrelated to the video, lately I've been trying to save fuel, and to do so I stay 10/15m from trucks going at 90km/h on the highway, to benefit from the drafting effect of it. I don't want to go any closer to it because it would be dangerous if the truck happens to brake suddenly, but I was wondering if it really made a difference at that distance. My car tells me I drop from 5.5L/100km to 2.9L/100km when I do it, but I don't know if it's really accurate. (maybe it's just a coincidence because other conditions were changing when I tried )
To be short, I'd like to know how close to a moving truck should you be to really benefit from the drafting effect ? ( Not saying I'm going to do it if the answer is "2 meters", I don't want to drive dangerously. )
Anyway, even if you never answer that question, keep up the good work, I'm really enjoying your vids! Cheers from France!
Guss,
You most likely need to be within the main wake of the truck to see the most benefit. My guess is that the length of the main wake is on the order of the width of the truck. So probably 3-4 meters. I wouldn't recommend driving this close.
I have tested this drafting method some time ago and i found that it depends on the shape and speed and your distance to the front truck, if its a big long container that moves fast and you run closely behind it youd get considerable cut in fuel consumption and you would immediately feel it by reducing push to the gas pedal by half to maintain your speed (specially for less aero sedanes like mine) and at the close distance youd easily feel the turbulance and unsteadyness of the stream behind the truck by a huge baffeling , a little more distance the stream become more stable, and if you increase your distance further more at a specific distance if you take down side widows you can feel the powerfull downwash vortex trailing the truck, farther from this point the drafting would be minimal
If there's any sense in the way your car's trip computer works this number out, then it'd take momentary fuel flow and speed, do some maths with it and spit out a number. At that very moment, it really is consuming that little fuel. The reason for this could well be sitting inside a lorry's wake, however it could just as easily be a gradient change, so I'd suggest repeating the experiment in more controlled conditions.
In my opinion though it's a veeeeeery bad idea. Motorways are boring. As you relax and settle into a long drive (especially sitting behind a lorry!) your reaction time doubles (or worse) and leaving yourself less than 1 second to react to whatever it is that's going on is not the way to go. Burn the extra fuel, stay safe!
I have a peugeot 206 with oem spoiler, would there be any improvement if I added a gurney flap?
Won't the gurney flap just on the rear cause a imbalance between the front and rear down force causing the car to push? Or is his car already loose in that turn?
Hello Sir Grays Garage! Adding a rear spoiler to a C7 Corvette 1LT is a good thing over all? Will it strain the engine, slow it up in a bad way or, etc.? And some important pros or cons? And overall install rear spoiler or not? Thanks! Here is link to C7 without spoiler and wondering if good to add rear spoiler to it? www.autoguide.com/new-cars/2017/chevrolet/corvette/1lt/2dr-stingray-cpe/
Couldn't a shark fin help his case a little bit? I don't think it would be legal, though.
What do you use for your figuring out aero?
Your model doesn't reflect real life.
Air flow over the roof of the VH travels diagonally over the rear of the roof not just parallel, and around the rear windows and is acting in 3 dimensions not just 2.
The problem with the VH (& VB to VL's) is they produce a lot of lift in standard form and get very floaty over 120km/h.
In the rain at high speed you can see water drops going up the side windows from the low pressure over the roof.
So your starting with a handicap before you add any aero improvements.
have you done an episode on roof spoilers on sedans, www.vparts.se/media/catalog/product/cache/3/image/400x/9df78eab33525d08d6e5fb8d27136e95/i/m/image_44722.jpg like this, and the effects of them, if not i would be interested in seeing an episode on them
take a look at episode 6, not quite the same as what you've posted. But you might be able to learn something.
hey I'm a 2nd yr. aeronautical student and expecting to built my own sports car please reply me