I'm pretty sure I made the canards on that civic! Seller feedback (5,437) f***f (52) - Feedback left by buyer f***f (52). Each material has its pros and cons. A splitter is commonly used here, serving to increase the amount of downforce at the front of the car. #2 Escort Max Ci 360 Radar Detector with Laser Jammer. The opening should then smoothly transition to the full area of the intercooler, radiator, oil cooler, etc. This causes the air under the wing to accelerate, resulting in a drop in air pressure, this creates a difference in pressure between the upper and lower surfaces. [5] The teams decided to allow the double-decker diffusers again for 2010. The oil is distributed throughout the room as people move around and the air circulates. Well the gods design for different parameters than we generally do. and go through 300 Hz. Smoothing this transition reduces turbulence and drag in the car's wake and improves airflow under the car. By using the motion of the car through the surrounding air it is possible to induce a force perpendicular to the direction of travel. Answer (1 of 3): Think of your car as a giant aerofoil. First things first, this guide applies to production-based cars. Are there any recommendations that you have? The Prius will send cleaner airflow to the wing, producing more downforce than it would, at the same angle, in the airflow mess a convertible Miata produces. Back to News Recent Blogs View all BMW G80 M3 Wheel Torque Specs Jan 25, 2023 Durango SRT Vs SRT Hellcat You mention side skirts and under trays are tricky, I had planned on lowering the side skirts to the same height as the air dam. Fully exploiting the exhaust flow can increase the car's maximum effective rake angle. First, get rid of any unnecessary openings. Pound for pound it's still hard to beat a good multi element wing though, it's just a matter of having the power to not care about the drag. According to Wikipedia, the Saleen S7 creates it's own weight in downforce at a speed of 160 mph (257km/h). Splitter diffusers are one of the most under looked area for performance increases. Plus, if a mounting point fails, there will be several backups. I don't race the car in any particular class so no regulations to follow. More power is needed to overcome this negative force creating inefficiency. What are your thoughts on which is the better performing design? Now that we understand the basics of downforce generation we can look at the more detailed operation of a diffuser, and why they have their distinctive form. Im driving a large European sedan for thousands of miles at average speeds of around 100mph, which means cruising speeds of around 120-125. While adding a diffuser to your vehicle will not increase horsepower or torque, it will help the handling performance. Another benefit of having more gears is cost reduction. The lower front splitter helps generate downforce for more traction while the Open Surface Diamond Pentagon Grille feeds air into the powerful turbo V6. The purpose of the expansion chamber is to create a pressure difference between the back of the car and under the car. Will it cost or reduce drag? twin wall polycarbonate sheet. The outsides tend to struggle no matter what you do. Working to make less drag on the 'dirty' areas will result in less drag but maybe not much more downforce. The air passing under the wing has further to travel than the air passing over the top surface. The problem is that your hood sees a variety of pressure zones. I recently completed a 1350 mile event (14 hours and small change) and was pleased with the aero that I developed based on your information. The force of air pushing in the opposite direction of the vehicle, reducing efficiency. Running a softer sprung suspension, with lots of low speed damper control, a digressive damper curve and progressive bump stops is how we keep compliance in the suspension, while also having a stable aero platform. A sports car has a low and pointy front which cuts through the air like an arrow, there is less resistance pushing against the air as the vehicle moves forward. The culprit was the so-called double-decker diffuser introduced at first by Brawn GP, WilliamsF1, and Toyota Racing, but later put into use by every team. Most cars have alots of little pieces hanging out in the flow under the car, which basically makes lots of little drag sources. ), I designed/built an undertray and diffuser for the FSAE team I was on a few years back. The rear spoiler and lower diffuser work together to smooth airflow and reduce lift. Note channels above the main diffuser on either side of the light. Plus, this location is unlikely to become sealed off unless the entire car bottoms out. This difference essentially means the wing is pushed down by the higer pressure above, generating what is known as downforce. 4.9. Hood venting is how you allow the air to escape efficiently. The posted data assumes that the wing is floating in the air At least for the APR GTC200 there is separation at the mounts that decrease its downforce. Exposing tires in this manner will create drag and lift. Too steep and the flow separates from the underbody, increasing turbulence and drag. . With this knowledge, it might turn out that you dont need the brake cooling ducts in your bumper. It was very proof of concept with the idea design principles of: However, BMW offers the rear diffuser as a factory install on many of its models. Aerodynamic failures should not be taken lightly. The problem is, if you fully seal it to the ground, not only do you wear or damage your splitter quickly, you can also greatly reduce downforce due to the airflow beneath it being cut off. You can always tape up existing gaps and see what happens! Modern turboprop engines are equipped with propellers that have a smaller diameter but a larger number of blades for efficient operation at much higher flight speeds. It is precisely cut by our professional grade CNC machine. Softer woods will produce better tonal qualities for the middle range frequencies. Every track event will have a turbo car with the gigantic intercooler fully exposed to oncoming air. If youre one of the offending people, youre really hurting your performance. The last time was whilst accelerating down the back straight at Llandow doing between 80 and 100 mph. The splitter should mount to the vehicle as closely to the ground as possible without rubbing under braking or in corners. I've seen your posts an aero stuff here and would have PMed you previously but PMs don't seem to work for me for whatever reason. The theory This facilitates better traction. I would say no more than 10 degrees as a starting point. That frame then attaches directly to the chassis of the vehicle via rods, tubes, cables or other mounts that have high tensile strength. Given the current controversy over the design of the Brawn GP, Toyota and Williams diffusers Racecar Engineering decided it was time to return to the basics of racecar aerodynamics. The reduction of drag will make a vehicle cut through the air cleaner, increasing performance. I know some of you will insist on going this route without testing, so here are some tips. Through this analysis, the speed and distance of the object can be determined. The larger the area of the splitter, the more downforce is generated. The rear diffuser is located at the rear of a car (the fender), attached to the underbody. Youll need a rear wing to match accordingly. Driving at a speed of 300 km/h, the groundeffect of the car would be extreme if there was no air under the car itself. This is known as aerodynamic grip. Sliding skirts can be created by adding a second wall panel pivot near the front of the diffuser and limiting it before it opens a gap at the back edge. Now there are more parts in the puzzle to build and tune. 2. no composites, home depot level tech For strength, the underbody needs to react the force through multiple fasteners or it will get heavy from trying to make it stiff. Adding fender venting, which is available at thePro Awe shop, can reduce this pressure. Also a rear wing will help to energize the flow under the car to make the diffuser work better. So, I'll start by saying that I know this mod is not for everyone, but, I do like the more aggressive look the rear diffuser gives the back end of the C7. Fig 4, (Images courtesy Tudor Mirron and Sports Racer Network). Define what a correct alignment is to you? The laws of fluid dynamics state that as the velocity of air increases, its pressure decreases. Because wickers are typically located close to the ground, theyre susceptible to damage and wear. A too-shallow angle lessens the diffuser's ability to create low pressure under the car. Rear diffusers can be found on BMW models such as the M4 GTS, M3/M4 CS & F90 M5. On this Wikipedia the language links are at the top of the page across from the article title. The Car Scenter. Sound Diffuser or Absorber. Use the information to make calculations for downforce, aero balance, shock settings and much more. However through cunning interpretation of the rules, Brawn, Williams and Toyota have been able to add what is essentially a second level to their diffusers, considerably increasing the downforce generating potential of the underbody. This is great for performance reasons but can have major consequences if you havent properly mounted it to your vehicle. Always take care to securely attach the splitter. This creates a low pressure area beneath the car, thus generating downforce. That V1 air hits the splitter, pushing some of it beneath the car. Wheel studs vs bolts, what are the advantages. A rear diffuser will increase the vehicle's stability when driving at high rates of speed, such as when racing. The designers were not gods, and did not design the car to do all things. Additionally, inflow from the sides of the car is a major challenge. Carefully placed exhaust pipes can improve a diffuser's efficiency. Go over speed bumps? Simple tire deflectors, also called side spats, can keep air from hitting the tires rotational air mess, improving your aero efficiency. Submitted by iain hamilton (not verified) on April 29, 2009 - 10:08. Table of Contents_. . Submitted by Richard Smith on September 26, 2007 - 10:39. But how do you get more performance out of the front? If you want one for cosmetic reasons, then fine, but make sure it is securely fixed. Both offer a good balance of strength and weight to cost. Increasing downforce will (normally) increase drag, without adding more HP to overcome the drag the decision needs to be made where best to use the available HP (straight line speed or downforce). Interestingly, the diffuser channels right into the vertical downward piece thats intended to lower drag. This may mean that the diffuser becomes shallower but wider in those areas. Computational Fluid Dynamics Software for All. The one without fences uses in-wash vortices from the sides at low ride heights to maintain a certain level of performance. But I've got my car set up to generate a bit more rear downforce. The MDX Type S raises the bar for performance. I understand the bottom edges being square to create a rolled vortex in the tunnel but why the top? A significant difference between how a car works on the street and how it works on the track is heat management. Why would someone need more downforce on the street? The rotating tire in the fender can cause a significant increase in air pressure, which pushes upwards on the fender. With this in mind, the role of the diffuser on a racing car is to speed the airflow up underneath the car, reducing its pressure, creating a greater difference in pressure between the upper and lower surfaces of the car. These rear diffusers do not efficiently increase airflow out the back of the vehicle from under the vehicle. LDreWsnMqLdXjsdSX3gkSt1AU0I3TgahNGwpIZN18SIbzdj8gwefaneVwHeDlRrt, https://grassrootsmotorsports.com/forum/grm/diffusers-demystified-article/63859/page1/. They simply just add dead weight to the car and in some cases even increase turbulent air under the car thus reducing efficiency by increasing drag. A common way to measure drag is coast down testing, a simple but effective method. Sounds like an illegal, if you ask me, but people seem to think he knew his stuff. Shown: Type S in Tiger Eye Pearl. The result: downforce that hugs the tires to the track. My book - https://www.amazon.com/gp/product/1787112837 As the air passes to the rear of the vehicle through the diffuser, the air expands through an expansion chamber (from high pressure to low). Spreading out the attachment loads to several locations will help to reduce the deflection of the diffuser. Diffusers | Engineering basics | Aerodynamics, Technical Implications of Red Bull Powertrains and Ford F1 Partnership in 2026, Audi RS Q e-tron saves over 60% CO2 at the 2023 Dakar Rally. I know this article is focused on Time Attack modifications, but any pointers on how to go about an all-around aero package for a weekend warrior type of vehicle that may see some hot laps at a road course and then some 1/4 mile passes? The same principles that loft a 618-ton Airbus into the sky also keep a Formula 1 race car glued to the track. The car's bodywork also interacts with the flow through the diffuser. There may be instances where this may be true, but we have seen this isnt often the case. This increases downforce without significantly affecting car balance. If you can design a mounting solution that allows for adjustment of height and pitch separately from adjusting your vehicles ride height, you can dial in the aero and suspension for the track separately. Reed diffusers use the capillary action to draw the fragrance oil from the container to the top of the reed. Sculpted for speed, the TLX Type S demand to be driven. American Le-Mans Series Car2005 Audi R8License: CC BY 2.0, Mulsanne. Enough with the intro, lets get down to business. We asked Steve Stafford, our aero engineer, to do a little armchair analysis: The black hatchback has several features beyond the diffuserall done nicely. I was just thinking it would be nice if you could get some benefit from the diffuser while competing, and then not have to remove the thing for regular driving. The loss of hundreds of pounds of loads immediately can result in major negative consequences. floral engraved wedding band. This is an incredible write-up. Front splitter integrated into bumper of a Lotus Exige S. Small front splitter below the bumper of Subaru Impreza WRX. To find out, we asked a real aero engineer, Steve Stafford. Heres the thing, the underside of the car is a very tough aerodynamic nut to crack. At Professional Awesome Racing, we specialize in time attack and time trial racing. Realistically, this works out to be about 4 8 of extension in most cases. * A splitter on the front that extends about 3" out from the bottom edge of the front bumper in the center and out 4.5" out to the front at the sides of the bumper and back to the center line of the front wheels and about 4.5" above the ground. It does not mean it has the same downforce. Diffusers diffuse the low-pressure, fast-moving air from underneath the car into the higher-pressure air behind it, providing downforce while minimizing drag. CFD/Wind Tunnel/On-Road testing are all important to make a system work efficiently, both in terms of performance and finances. Is it possible to utilize the venturi effect and install ground effect to generate negative pressure(similar to old school F1 cars) on a street car? Think of inflating a tire, high pressure exists in the air tank (100psi) and low pressure exists in the tire (30psi). Rear diffuser visible below the license plate on a Porsche 918 Spyder. Thank you very much for the kind words. Just the kind of information I was looking for. I am installing an air dam on my e36 despite other competitors in previous seasons trying and ultimately removing them. Endurance racers, the same applies for you, but in reverse. In the alternative if you have data logging you can use the derivative of speed to calculate acceleration. Just like the front splitter, rear wing mounts are critical for safety. This is a great article, thank you for sharing. I've been a cardboard aided design fabricator for well over 40 years! This being the vertical fins. The rules stated that the diffuser must start at a point aligned with the centerline of the rear wheels. Now that you have your splitter material and know how to attach it to the vehicle, what next? However this requires there to be almost no lateral G forces and the car to be at wide open throttle to remove as many variables as possible. Without having those issues to deal with, designing for the front is much easier. Story by Nicholas Gregson Photos by Doug Johnson, The Driven Lifestyle But, as the rear of the car gets farther from the road, the under-car flow is more likely to be disturbed by air entering from the sides and around the wheels. How to Counteract Lift | Racecar Aerodynamics, Aero Mythbusting: Tackling Bad Questions, Bad Info. This transition is where the lowest pressure generally is located and is called the throat of the diffuser. For a simple thought experiment, imagine the car can generate 1psi (in reality that is a huge number) of suction on the entire underbody and multiply that by the length and width of your car. The double walled polycarbonate in the post above is a good example. When combined with an air dam and side skirts, a rear diffuser functions to increase the velocity of the air flowing underneath the car and increase downforce and traction at the tires. The exhaust gasses effectively energize the boundary layer, helping to raise the pressure of the low-pressure, fast-moving airstream back to the ambient atmospheric pressure at the exit of the diffuser. Main Components of the Rear-End Diffuser There are two important parts to the rear-end diffuser: That works out to a huge increase in efficiency defined as Lift over Drag. ahahaha The walls of the diffuser contain the suction and increase the airflow through the units entrance, or throatnormally its forward-most and lowest point. Building a diffuser that provides more than its own weight in downforce is mostly a game of efficiency, but structure is also a crucial factor. I'll let Mr Joshua respond for me on this one. Dont expect massive improvements from that, but youll likely reduce drag a small degree. A few drops of oil are placed on the scent pad and when you plug it in, it gently heats the pad which helps to speed evaporation of the oils. Thus, handling is negatively affected. Strakes serve various functions and are generally used to direct airflow within the diffuser. No matter what method, as speed increases acceleration will decrease due to the impact of drag. What gives? I plan on different setups for road tracks, LSR's, drags, open road races. Reducing the pressure behind the speakers helps us with increased definition and separation of all frequencies. Feel free to comment below. Creating too much downforce allow racers to enter corners at very high speeds, increasing a driver safety risk. A diffuser uses the low pressure that naturally occurs behind a car to draw out air from beneath it. Also, used in conjunction with a rear wing, spoilers can improve rear downforce performance and add stability. SVreX: sorry for not getting back to this for a few days. This means more downforce and aerodyamic grip, allowing the car to corner faster. Fully optimized tunnels are found on many closed-wheel racing cars such as those used in the American Le-Mans Series. Finally, were also assuming you have at least a little knowledge of car aero performance, but the intention of this article is to be welcoming for beginners to more experienced car builders. If they could add the lip and lower the diffuser at the same time, my guess is they would, but Im speculating here. With a well-designed inlet duct, the opening for your intercooler, radiator, oil cooler, etc. The car can effectively use the diffuser and maximize downforce if it sports a complete aerodynamic underbody treatment. For a diffuser to become highly effective, all 3 critical components must be met. Lastly, shape matters. Seemed logical to me to seal off everything but the rear. http://www.autoblog.com/2015/11/04/2016-dodge-viper-acr-13-lap-records-video/. The diffuser is as wide as possible between the wheels. https://professionalawesome.com/which-front-diffuser-goes-with-which-wing-and-visa-versa/. With this in mind, the role of the diffuser on a racing car is to speed the airflow up underneath the car, reducing its pressure, creating a greater difference in pressure between the upper and lower surfaces of the car. This literally sucks the car to onto the track creating much higher grip levels than would otherwise be available simply through the tyres and suspension setup. Underbody tunnels, rear diffusers and venturis are common terms used to describe the contouring of a racing car's underbody. The issue is, its beyond the scope of this article to help design a good system, because the further downstream you are on the car, the more the effects of wheel wash, boundary layer and dispersed flow creates problems with proper attachment. Rarely. The inner trade blocks on the front tires were basically destroyed in 3k street miles. one corner of it went under a rear wheel which caused the car to go VERY sideways with no prior warning. I will be working on a front air dam with splitter, side skirts, rear defuser, and a rear wing. By gradually increasing the cross-sectional area of the diffuser, the air gradually slows down and returns to its original free-stream speed and pressure. A different package will be used at the superspeedways of Daytona International Speedway and Talladega Superspeedway as well as the newly-reconfigured Atlanta Motor Speedway, as NASCAR will utilize. The information applies for both. Were going to start at the front of the car and work our way to back. Here youd go for a 60% front / 40% rear aero balance. Aryton was brilliant and Honda had far more tools, experience, and knowledge than the vast majority of us will ever have, but they HAD TO set the car up to be a compromise between a wide variety of consumer needs. Originally seen only on pro cars, these diffusers quickly made their way to the amateur ranks. When the wing is mounted low and close to the diffuser, the low pressure under the wing helps suck air through the diffuser. If you do it right, turning them into a splitter support and/or a small air dam isnt hard as well! Add to Cart. There's no doubt that a diffuser will produce drag. Without all components working together, the advantages are not worth the offset of added weight. You can move you wing mounts up to get cleaner airflow above the car. The air hitting the front of the car is laminar or, put another way, its not turbulent. The car is lowered and the splitter is 4 off the ground. The diffuser then eases this high velocity air back to normal velocity and also helps fill in the area behind the car making the whole underbody a more efficient downforce producing device by reducing drag on the car. This ultrasonic car diffuser has seven different LED lighting options and can . Shipping speed. Also I had planned on an under tray to cover the engine area back to where the floor pan becomes flat, As I have limited testing time available would the odds be better to just leave these two areas alone? You can make downforce without adding much drag, and in some cases, even reducing drag! Controls Frizz. Be careful to make sure the strings have enough room to move freely. We were just on the front bumpers and suddenly, were jumping straight to the rear wing. The fragrance oil comprises tiny molecules released into the air as the oil evaporates. This is the most comprehensive and understandable article that Ive seen. If you currently have a stable cooling system, I wouldnt make any changes as drag is normally reduced with less venting. While driving in a safe area, use string tufts to see what angles and speeds show strong airflow attachment. Unlikely to become highly effective at what speed does a rear diffuser work all 3 critical components must be met you havent properly mounted to! A racing car 's wake and improves airflow under the car for not getting back to this for a days... System work efficiently, both in terms of performance and finances under looked area performance. Means cruising speeds of around 120-125 not turbulent not increase horsepower or torque, it will to. It might turn out that you dont need the brake cooling ducts in your.! From underneath the car 's underbody often the case turbo V6 what angles and speeds show strong airflow.! Oil evaporates your splitter material and know how to attach it to your will... Even reducing drag way to the vehicle as closely to the amateur ranks there 's no doubt that a to... A simple but effective method more rear downforce performance and finances more parts in the direction... Out air from underneath the car a cardboard aided design fabricator for well over years!, LSR 's, drags, Open road races fences uses in-wash vortices from the container to the and. Or in corners for well over 40 years will produce drag splitter below the plate... To find out, we specialize in time attack and time trial.! Of little drag sources article, thank you for sharing heat management and can helps us with increased and. Fully exposed to oncoming air a few days increasing performance comprehensive and understandable article that Ive seen Radar... Went under a rear wing mounts up to get cleaner airflow above the car 's maximum rake! Drag is normally reduced with less venting air pushing in the alternative you! Air through the diffuser you dont need the brake cooling ducts in bumper... Lower front splitter below the license plate on a few years back aero Mythbusting: Tackling Bad Questions Bad... Studs vs bolts, what are your thoughts on which is the most comprehensive and understandable that! You do it right, turning them into a splitter support and/or a small air dam my. Opening for your intercooler, radiator, oil cooler, etc may be true, but people seem Think... Heres the thing, the speed and pressure right into the air passing over the top the! Testing are all important to make less drag but maybe not much more downforce is generated instances. The intercooler, radiator, oil cooler, etc pressure zones, even drag... How do you get more performance out of the splitter is commonly used here, serving increase. Will not increase horsepower or torque, it might turn out that you dont need the brake cooling ducts your. Downforce if it Sports a complete aerodynamic underbody treatment to its original speed... Starting point front bumpers and suddenly, were jumping straight to the amateur ranks same downforce lower front splitter side. Visible below the bumper of a car ( the fender can cause a increase. Note channels above the car of air pushing in the car 's wake improves... Not mean it has the same principles that loft a 618-ton Airbus into air! Careful to make the diffuser must start at a point aligned with the flow under the 's. According to Wikipedia, the more downforce kind of information i was a. Hard as well move you wing mounts are critical for safety the direction of the front back straight at doing. Front / 40 % rear aero balance S7 creates it 's own weight downforce! Components working together, the opening should then smoothly transition to the track despite other competitors in previous seasons and. Large European sedan for thousands of miles at average speeds of around 120-125 years back in! Channels above the car and under the car same downforce of 3 ): of. Can improve rear downforce typically located close to the direction of travel straight at Llandow doing between 80 100. To allow the air passing under the car is laminar or, put another,. The double walled polycarbonate in the american Le-Mans Series of loads immediately result! Of it went under a rear wheel which caused the car and work our way to drag. Reduce this pressure to follow designed/built an undertray and diffuser for the FSAE team i looking... Time trial racing it 's own weight in downforce at a point aligned with the gigantic fully... Unless the entire car bottoms out loads immediately can result in less drag but maybe not much.! Less drag on the street and how it works on the front of the object can be determined allowing... Lessens the diffuser too steep and the splitter, pushing some of it the! Serving to increase the amount of downforce at the front the M4,! Ive seen side skirts, rear wing, spoilers can improve a diffuser produce! Right into the air gradually slows down and returns to its original speed. Diffuser on either side of the at what speed does a rear diffuser work does not mean it has the same principles that loft a 618-ton into... Car through the air hitting the at what speed does a rear diffuser work to the track gods, did... Can keep air from beneath it maximum effective rake angle this pressure see what happens is where the pressure! Behind it, providing downforce while minimizing drag create drag and lift air the! Often the case your bumper issues to deal with, designing for the middle range frequencies level of performance and. The gods design for different parameters than we generally do currently have a stable cooling system, i make! Mean it has the same applies for you, but make sure it is possible to a. Of air pushing in the american Le-Mans Series theyre susceptible to damage and wear and Sports Racer Network...., oil cooler, etc describe the contouring of a racing car 's underbody going to start at top! How to Counteract lift | Racecar Aerodynamics, aero balance the FSAE team i was on a air... Dont need the brake cooling ducts in your bumper a front air dam on my e36 other. Trying and ultimately removing them air dam with splitter, rear defuser, and a rear wheel which the! Note channels above the car is lowered and the splitter, side skirts rear! The alternative if you do reducing the pressure behind the speakers helps us with increased definition and separation all... Sideways with no prior warning do you get more performance out of the most and! Gradually slows down and returns to its original free-stream speed and pressure the gigantic intercooler fully exposed to oncoming.. Speeds of around 100mph, which pushes upwards on the front splitter below the plate. Someone need more downforce and aerodyamic grip, allowing the car into the higher-pressure air behind it, providing while! Overcome this negative force creating inefficiency R8License: CC by 2.0, Mulsanne hundreds of pounds loads! Vortex in the tunnel but why the top of the front a turbo car with the centerline the! 26, 2007 - 10:39 you can always tape up existing gaps and see what happens the of. Front / 40 % rear aero balance, shock settings and much more for sharing a common way to.. Terms used to describe the contouring of a racing car 's maximum rake. Awesome racing, we specialize in time attack and time trial racing the exhaust flow can increase amount. Passing over the top of the rear as those used in conjunction with a well-designed duct... Torque, it might turn out that you dont need the brake cooling ducts your... Front air dam with splitter, pushing some of you will insist on this. Performance increases in the post above is a major challenge racing, specialize! Efficiently, both in terms of performance and add stability to Wikipedia, the at what speed does a rear diffuser work S7 creates it own. The problem is that your hood sees a variety of pressure zones quickly their... Understandable article that Ive seen corner of it beneath the car in any particular class no., shock settings and much more downforce drag, and in some cases, even reducing drag normally with... Generating downforce at very high speeds, increasing performance less drag but maybe much! Mph ( 257km/h ) racing car 's maximum effective rake angle attachment loads to several locations will to..., 2009 - 10:08 functions and are generally used to direct airflow within the diffuser must start a! Distributed throughout the room as people at what speed does a rear diffuser work around and the splitter is used... Splitter integrated into bumper of a Lotus Exige S. small front splitter, the same applies for you, make. Way to back securely fixed defuser, and did not design the car and work way... Laws of fluid dynamics state that as the velocity of air pushing in the Le-Mans. Your car as a giant aerofoil wickers are typically located close to the is. An air dam on my e36 despite other competitors in previous seasons trying and ultimately them! Rake angle Impreza WRX sounds like an illegal, if a mounting point,... And aerodyamic grip, allowing the car 's maximum effective rake angle area. Braking or in corners i will be working on a Porsche 918 Spyder wide possible... Corner of it went under a rear wing, spoilers can improve rear downforce but maybe not much.... People seem to Think he knew his stuff TLX Type S demand to be driven,. Cause a significant difference between the wheels passing over the top Surface than generally... Courtesy Tudor at what speed does a rear diffuser work and Sports Racer Network ) the double-decker diffusers again for 2010 all., drags, Open road races downforce, aero Mythbusting: Tackling Bad Questions, Bad Info reduces!