Lando Norris, McLaren, Bahrain International Circuit, 2021

McLaren surprised rival teams haven’t adopted unique diffuser design

2021 F1 season

Posted on

| Written by and

McLaren technical director James Key admitted he is surprised no other team has adopted their solution to the new diffuser regulations.

The change to the diffuser dimensions was one of three restrictions imposed to reduce how much downforce cars generate this year. It required teams to reduce the height of the vertical strakes within the diffuser by 50mm.

However McLaren have carefully exploited the regulations specifying the dimensions of different parts of the diffuser which allow them to have longer strakes provided they are situated within 250mm of the car’s centre line.

The detail was hidden by McLaren in images they issued from their car’s filming day at Silverstone, and came to light when testing began in Bahrain last week. The team’s technical director James Key admitted he expected other teams would have interpreted the rules in the same was as McLaren.

“I think we are a bit surprised that maybe we’re only team right now with that,” he said. “It’s just one feature of many on an area which changed for this year.”

Key credited the team’s aerodynamic department for coming up with the novel solution.

“I think it’s always nice for a team to come up with an idea which is unique and the credit fully goes to our aero department and the guys in the rear aero group for realising that there was an opportunity there to use the new regulations in such a way. So full credit to them in that respect.

McLaren MCL35M rear wing, Bahrain, 2021
McLaren’s unique diffuser strakes were spotted at the start of testing

Advert | Become a RaceFans supporter and go ad-free

“Of course it’s nice to find something which is maybe a little bit unique to us. I suppose it’s one of those visible things which gets talked about a lot, but ultimately it’s just a bit of a much wider picture of a complex back of a car. I’m sure it’ll be forgotten by the time we get back here in a couple of weeks’ time.”

Key suspects it could take a few weeks for any rivals who wish to copy McLaren’s design to produce a version tailored to their cars.

“The first port of call with any any idea you see elsewhere is CFD,” he explained. “So I think you can jump on an idea that you spot on another team within a week, easily, nowadays.

“If there’s still interest after a week, whether it’s our diffuser or Mercedes’ edge of floor detail or whatever it is, I think you can get a feel for things quite quick.

“Then it’s really understanding how it works with your car. That’s the key to this, so you can end up with a unique geometry of your own because you might understand the principle, but then you have to adapt it accordingly that it works with your car. And the diffuser situation, for example, is also very stable in that environment as well.

“So you’d probably, therefore, wind tunnel test it, so that might be a week or two down the line. And then you’ve got to a manufacture it – and these particular purposes are fairly straightforward so you could say between three and five weeks between taking the picture and putting it on your car if you really wanted to push it through.”

Advert | Become a RaceFans supporter and go ad-free

2021 F1 season

Browse all 2021 F1 season articles

Author information

Dieter Rencken
Dieter Rencken has held full FIA Formula 1 media accreditation since 2000, during which period he has reported from over 300 grands prix, plus...
Hazel Southwell
Hazel is a motorsport and automotive journalist with a particular interest in hybrid systems, electrification, batteries and new fuel technologies....

Got a potential story, tip or enquiry? Find out more about RaceFans and contact us here.

11 comments on “McLaren surprised rival teams haven’t adopted unique diffuser design”

  1. I really enjoy the insight he gives us on copying this. 3 to 5 weeks isn’t much.

    1. Usually not, but it’s a different story this season. Teams need as much time as possible for CFD and wind tunnel, that they can’t afford to loose any of it on this year’s car.
      Mercedes and RB might copy it though, as they are fighting for the championship this season.

  2. Most big teams are probably designing & testing it right now!

  3. Honestly, Mclaren has been the team that has impressed me the most in this pre season test. They were the only team to switch to a new engine supplier, yet, they were the first to reveal their car and they finished the pre season test with no failures with a decent number of laps covered. They are also the only team to find a loophole and create a unique solution to one of they key performance areas – the diffuser.

    They’ve been on an upwards trajectory since 2018.. and they seem to be finding the form again that made them one of the most formidable teams in the paddock. If they can consistent progress over this season and make another step forward next winter, I don’t see why they can’t be fighting for wins and podiums consistently.

    1. And could make Danny Ric’s move look inspired!

      1. @muzza I mean, given his former team Red Bull might be the pack leader (I still refuse to believe Mercedes won’t dominate), I still think his best option would have been to stay at Red Bull and hope to pull a Rosberg on Max.

        1. That’s probably true, didn’t think of it this way, but I also agree that until the results start backing up ricciardo’s move, he gave up the chances to get some wins per season to get some podiums.

        2. No one on that grid today could out perform Max, (unless you have a dominant car like petronas) let alone Daniel Ric.

      2. I would love to see Danny Rick win more races this year.

  4. Alpine has said anything can be copied within 2 days so beware of what you wish for?

  5. If the McLaren new diffuser design works, will one of the other teams lodge one of those passive aggressive ‘clarification’ requests?

Comments are closed.