WRCWings Profile picture
Aug 18, 2022 9 tweets 6 min read Read on X
Do you know why #Rally1 cars have such high wheel arches? And why Toyota and Hyundai's rear arches are the only exceptions to this trend? Aerodynamics is behind it, read on this thread to find out why.... 📸by @MSportLtd #WRClive #WRCliveES #WRCjp #YpresRally Image
Removing air from the wheel well (and therefore the underbody of the car) is a clever way to reduce the pressure under the car. As the pressure on the car remains constant, the force pushing the car towards the road increases (more downforce = more grip). Image
In the 2017-2021 #WRC car generation, the air was extracted from the wheel well through the rear fender vents... How can we forget the CD holder on the Toyota Yaris WRC/ Ford Fiesta WRC, or the vertical air vents on the Hyundai? Image
The regulations for 2022 banned fender vents, forcing teams to search for alternative air extraction, so they increased the space between the wheel arch and the tyre, eliminating the side protection 📸by @HMSGOfficial Image
With this design, the air has a larger area to escape from the wheel well, reducing the pressure under the car. So why isn't the Toyota's rear arc as high? Because there the air has another alternative to escape📸by @TGR_WRC Image
Inside the rear wheel arch of the Toyota is an internal duct that carries air to the rear bumper, on either side of the hybrid cooling system fans. The air coming out of this duct is drawn in by the air expelled by the cooling fans and sent to the rear of the car. Image
Ultimately, the cooling system's fans indirectly help to draw air out from under the car, thus generating some downforce, and making the use of high rear wheel arches unnecessary. Image
In the case of the Hyundai i20 N #Rally1, the rear arch shows a mixed design, but still with a large open space at the front to allow air to escape. Image
This is especially important in tarmac events such as the @ypresrally, where car ride height is minimal, and any contribution to reducing the pressure under the car will translate into better grip, i.e. higher speed, especially in the corners. 📸by Nacho Mateo / @Motor_Esport Image

• • •

Missing some Tweet in this thread? You can try to force a refresh
 

Keep Current with WRCWings

WRCWings Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us!

:(