Aero design of the 2022 Ford Puma Rally1

M-Sport Ford World Rally Team (WRT) started today the first development tests of the 2022 Puma Rally1 that take place outside their home test area (at least for what we know). The tests have been developed in Central Finland, close to some stages of Rally Finland.

The first images from the tests reveal some important modifications, with respect to the car that MSport presented last month at the Goodwood Festival of Speed. The main modifications can be identified at the rear of the car, but also some minor modifications at the front can be observed.

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Tuomas Töyry

The aim of most of the modifications is to compensate for the reduction of aero parts at the rear that 2022 regulations promote. The absence of a real rear diffuser will reduce the amount of downforce the new cars will be able to generate, in comparison with current cars. This explains why teams are working on the improvement of those parts still to be used in 2022, such as the rear wing, in order to obtain as much downforce as possible, thus reducing the gap in performance with respect to the current generation that new regulations will cause.

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Henri Vuorinen

The new rear wing still includes the two small wings on both sides (see yellow arrow in the image below), but with a higher angle of attack. An increase in the angle of attack of an (inverted) wing results in an increase of the downforce the wing is able to generate (up to a certain angle). But it also increases the drag (air resistance) due to the increase in the front area. Thus, the modification of the side wings introduced by MSport will contribute to increasing downforce (improving cornering speed), but at the cost of increasing drag (reducing top speed on straights).

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Tuomas Töyry

Note that the size of the endplates of the side winglets has significantly increased, due to the higher angle of attack.

Previous (left) and new (right) Puma Rally1 rear wing – images by @RallyngUK (left) and Tuomas Töyry (right)

The second modification in the rear wing affects the central, upper wing: the original wing has been replaced by a new one, straight at the back (while the previous was round), and also, with a higher angle of attack.

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Tuomas Töyry

The images also show the design of the rear of the car, under the rear wing. The air vent for hybrid cooling air removal has been redesigned, and now it has the shape of a trapezoid (a). It is still located over the rear bumper (b), which has now been modified, having now the shape of a rear diffuser. But it is not a real diffuser, it is just a modified rear bumper with a very low impact of downforce, as it is very short and with a very high angle. To be effective in removing air from under the car, it should be longer and with a smaller angle, such as the diffusers of the current cars.

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Hannu Rainamo (Hannuphoto)

The images from the rear also show that the design of the rear fenders has changed. One of the main features is that they now include channels on the sides (c), probably designed to allow airflow to remain attached to the car for longer, which in the end reduces drag.

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Tuomas Töyry

Another important modification can be found on both sides of the car: the side skirts are not flat anymore but have a small angle of attack, and they are connected to the small dive planes located ahead of the rear wheels. The result is probably a decrease in drag (due to the smoother design). In terms of downforce, the sloped side skirts are less effective in their role of preventing air from entering under the car. But, at the same time, the sloped skirt also generates some downforce thanks to the pressure exerted by air flowing over them. Thus, the resulting impact on downforce is probably neutral.

With this new design on the sides of the car, the rear brake air intake would be less effective. This is probably the reason why they have been removed from the Puma Rally1 car seen in the test.

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Henri Vuorinen

The Puma Rally1 tested in Finland includes small side mirrors (not present in the car seen in Goodwood).

M.J.Wilson/S.Loudon, Ford Puma Rally1, Development test, Central Finland – image by Tuomas Töyry

There are also modifications at the front of the car: both sides of the front splitter have been modified, in order to force air to flow upwards, over the front fenders, instead of flowing on both sides of the car. This allows generating some more downforce at the front, while the drag is reduced, as the air escaping from over the front splitter does not interact with the main air current flowing on both sides of the car.

And the bonnet vents have been relocated: now they are positioned behind the front lights.

In summary, the car seen in the test looks like a more developed version of the Puma Rally1, with some interesting solutions to compensate for the loss of downforce resulting from 2022 regulations. Many test sessions await him, but it is probably that this is the almost definitive version of the car that will take part in 2022 WRC Championship.

6 thoughts on “Aero design of the 2022 Ford Puma Rally1

  • 2021-08-04 at 08:30
    Permalink

    Honestly, the rear wing looks more and more like a Formula D/Pikes Peak car! However, the rear cooling inlet seems to still be rather unrefined; will you assume there’s going to be a new design before the final homologation? Also, it’ll be interesting how the teams tackle the inevitable understeer-fest due to the front downforce limitation. Not sure this is curable through pure set-up work.

    Reply
    • 2021-08-04 at 15:14
      Permalink

      First time I saw the rear wing, it reminded me that of the Audi Sport Quattro S1, Kevin! Regarding the rear vent, it may well be that this is the final design… although they still have five months to change it. But MSport normally maintains the original design of the new cars they design (as we saw with previous cars), so I don’t expect changes, unless it proves to be wrong.
      Understeering will be a major issue in 2022, yes, so they will have to get a very good balance of the car, which sometimes means to reduce downforce at the rear to equilibrate. Once the cars will be homologated, playing with rake will be the only tool they will have to improve it.

      Reply
  • 2021-09-01 at 09:33
    Permalink

    Hi Luis,
    Very good post as always!
    I have something I’ve thinking since the first 2022 prototypes. Do you think is there anyway that they can take advantage of the side intakes going to the back to create downforce? Or something crazy like the Brabham BT46 making some low pressure under the car? It sounds ridiculous for gravel as it would be a dust-blower machine, but maybe for tarmac haha

    Reply
    • 2021-09-01 at 16:04
      Permalink

      Hi Gabriel, thank you for your kind words! You go in the right direction: you can take advantage of the cooling air… but after the radiators. Before them, you need to minimise the pressure drop, to maximise its cooling efficiency. After crossing the radiators, and with the aid of fans, the air is sent to the rear of the car (through the rear bumper openings), adding energy to the air flowing from under the car and contributing to remove it faster (same as it is done with the centered exhaust pipe in the current generation, on top of the rear diffuser (exhaust blown diffuser concept). Removing air faster from under the car means to decrease the pressure, which results in higher downforce…. in a certain manner, similar to what Gordon Murray tried to do with the Brabham BT46. And yes, it is mainly effective at low ride height, that is, on smooth tarmac.

      Reply
      • 2021-09-02 at 08:09
        Permalink

        Thanks for the reply! Very well explained.
        Interesting also the low high ride part at the end after watching the Yaris that looks significantly higher than the Puma. Good to see different approachs to the same regulations.

        Reply
        • 2021-09-09 at 17:17
          Permalink

          Thanks Gabriel! In our latest article, we try to explain the design of the Toyota ride height, hope that you enjoy it!

          Reply

Leave a Reply

Your email address will not be published. Required fields are marked *