McLaren MCL39

[Hoffman900]

https://d3cm515ijfiu6w.cloudfront.net/w ... nsion1.jpg

Looking at how much higher the front lower wishbone is to the rear lower wishbone raises the question of how much anti-dive this car actually has.

They don’t have anymore than they ever had.

Anti-dive geometry has mattered in racing well before aero was a thing, and it was one of the first things teams design around as the car’s pitching under braking has always been noticable. It also matters in ever racing car that isn’t even aero driven. Heck, I have chassis design books from the 1970s that talk about anti-dive in relation to aero.

Too much anti-dive causes jacking. There are practical limitations of how much you can have.

99% of what you’re seeing is related to aero and aero alone.

F1 cars have maybe 30mm of front deflection, with half of that from the tire alone. So you’re left with ~15mm of travel to control. Under braking, you’re not using all of that, so now you’re talking 3-5mm under braking. A few percentage (or 10-20%) anti-dive difference would be near neglible. My point being, the arms are located where they are, mostly for aero. Aerodynamcists mostly dictate where these arms are, and it’s up to the chassis guys to make it work.

[Hoffman900]

Scarbs talking about McLaren’s track rods

Scarbs makes nice illustrations, and seems like a nice guy, but he has no technical background and no motorsports experience.

[Andi76]

Here the two interesting drawings from Scarbs which also show where the Track Rods are:

https://d3cm515ijfiu6w.cloudfront.net/w ... nsion1.jpg

Looking at how much higher the front lower wishbone is to the rear lower wishbone raises the question of how much anti-dive this car actually has.

They don’t have anymore than they ever had.

Anti-dive geometry has mattered in racing well before aero was a thing, and it was one of the first things teams design around as the car’s pitching under braking has always been noticable. It also matters in ever racing car that isn’t even aero driven. Heck, I have chassis design books from the 1970s that talk about anti-dive in relation to aero.

Too much anti-dive causes jacking. There are practical limitations of how much you can have.

99% of what you’re seeing is related to aero and aero alone.

F1 cars have maybe 30mm of front deflection, with half of that from the tire alone. So you’re left with ~15mm of travel to control. Under braking, you’re not using all of that, so now you’re talking 3-5mm under braking. A few percentage (or 10-20%) anti-dive difference would be near neglible. My point being, the arms are located where they are, mostly for aero. Aerodynamcists mostly dictate where these arms are, and it’s up to the chassis guys to make it work.

Thank you very much. Finally someone who speaks plainly. All this talk about anti-dive just because the position of ONE attachment point is different - that's just nonsense. Unfortunately, this misconception has been spread for years by so-called experts who should actually know better, but obviously have no idea about suspensions and suspension geometries. A lower rear mounting point of the upper wishbone alone lowers the lateral instant center, which actually reduces the anti-dive value, not increases it. In addition to the other mounting points, the CoG Height, Side Swing Arm Length and Break Bias play a decisive role. Likewise, as you rightly say, too high an anti-dive value causes problems and drastically reduces the feeling and feedback for the car that is important for the driver, which is why it is not desirable to have too much anti-dive. This is a technical forum and just like experts should not spread uneducated things here. So thank you for your clarification, which is absolutely correct! Why F1 "experts" spread such nonsense I don't know. Someone like Gary Anderson, you can think what you want about him, should actually know as a former technical director of an F1 team that the suspension of every car does not consist of just one mounting point and that looking at a single mounting point says about as much about it as a single flap of a wing says about the overall aerodynamics of a car.

However, what you say about Scarbs is not correct. If memory serves he attended Hendon College of Further Education from 1984-1986 and studied engineering there. Nor would I say that someone who has been following the technical side of motorsport since the 1970s and deeply since the late 1990s and who has been in and out of the pit lane and worked for Prodrive has no motorsport experience.

[Farnborough]

From that schematic, it would look like there'd be need of a "bell crank" arrangement at the steering rack end where is exits the chassis. Without which it could move the control arm just outwards rather than linear "push" to move the wheel assembly. In effect, it's of this arrangement at the wheel end by the geometry offered in that drawing, this by the detail it looks to have..

If the steering arm passed outside the wheel upright centre (effectively rewards of that on chassis layout) it would in effect use the upright as the outer bellcrank, that's according to the schematic presented.

Perhaps this is what the area is that Zac was alluding to in more radical approach.

[Farnborough]

He also spoke of potential vulnerable attribute in risk to track rod end, which doesn't look any different in reality. In the classic "clip" of the barrier at right turn exit of Monaco swimming pool (the usual place for snapping such item ) it wouldn't appear to change that risk.

If it did use a bellcrank at inner end though, that ratio could be changed for use at Monaco hairpin for which they've historically needed a unique steering rack to get around.

[FittingMechanics]

In a strange twist of fate, I'm linking a reddit thread where former RBR engineer explains the steer sweep Lando did during the test. In short, they want to get aero map measured with the effect only of the wheels being sideways but the car still going straight (as much as it can). So the driver does quick steering movements so that the car doesn't grip up and turn.

https://www.reddit.com/r/formula1/comme ... technique/

[Hoffman900]

However, what you say about Scarbs is not correct. If memory serves he attended Hendon College of Further Education from 1984-1986 and studied engineering there. Nor would I say that someone who has been following the technical side of motorsport since the 1970s and deeply since the late 1990s and who has been in and out of the pit lane and worked for Prodrive has no motorsport experience.

Craig’s entire career is in non motorsports corporate IT. His work at Prodrive was leading tours to corporate and students. You can check his Linkedin.

But yes, all this talk of anti-dive is silly. If memory serves me right, it started on Reddit. I’m sure the teams were more than happy to let the media blab away about it knowing that’s what it wasn’t.

The Lotus 72 (1970) had 100% anti-dive and anti-squat with the sole purpose of controlling the aero platform. It handled terribly so they ended up dialing it back, but people have been thinking about it in relation to aero for over 55 years now.

https://www.motorsportmagazine.com/arch ... the-field/

[the EDGE]

However, what you say about Scarbs is not correct. If memory serves he attended Hendon College of Further Education from 1984-1986 and studied engineering there. Nor would I say that someone who has been following the technical side of motorsport since the 1970s and deeply since the late 1990s and who has been in and out of the pit lane and worked for Prodrive has no motorsport experience.

Craig’s entire career is in non motorsports corporate IT. His work at Prodrive was leading tours to corporate and students. You can check his Linkedin.

Is there a point to arguing over Craigs credentials? Over the years he has been of great benefit to Formula One technical analysis both on this very site, through his own channels, and with professional publications including appearances on sky F1. In fact here we are right now discussing his illustration

Gary Anderson used to be a technical director, but people complain about him too. Perhaps we should be invite Adrian Newey to Analyse the field, but I still suspect some would not be happy

[Hoffman900]

However, what you say about Scarbs is not correct. If memory serves he attended Hendon College of Further Education from 1984-1986 and studied engineering there. Nor would I say that someone who has been following the technical side of motorsport since the 1970s and deeply since the late 1990s and who has been in and out of the pit lane and worked for Prodrive has no motorsport experience.

Craig’s entire career is in non motorsports corporate IT. His work at Prodrive was leading tours to corporate and students. You can check his Linkedin.

Is there a point to arguing over Craigs credentials? Over the years he has been of great benefit to Formula One technical analysis both on this very site, through his own channels, and with professional publications including appearances on sky F1. In fact here we are right now discussing his illustration

Gary Anderson used to be a technical director, but people complain about him too. Perhaps we should be in by Adrian Newey to Analyse the field, but I still suspect some would not be happy

It matters when they position themselves as experts and share misinformation (and often not on purpose) and then people on the internet just keep repeating it, without questioning it, until it becomes internet fact.

Sam Collins is another one. He has an engineering degree, has work for Race Car Engineering (the publication), but haven listen to him talk over the years, I don’t think I’d let him anywhere near a Club Formula Ford, let alone anything else.

This all sounds harsh, but people need and should fact check everything and some of it is pretty easy to do.

How many people online spouting about anti-dive know that too much causes weight jacking issues? Or that too makes for a terrible handling car? Or that F1 designers have been using / playing with it with the sole purpose of controlling the aero platform since 1970?

It’s not a new concept, at all, and teams in 2022-2025 didn’t suddenly “fix” their issues by just adding more. It’s not as simple as “oh they’re running more anti-dive, why didn’t I think of that?”.

[the EDGE]

It matters when they position themselves as experts and share misinformation (and often not on purpose) and then people on the internet just keep repeating it, without questioning it, until it becomes internet fact.

Sam Collins is another one. He has an engineering degree, has work for Race Car Engineering (the publication), but haven listen to him talk over the years, I don’t think I’d let him anywhere near a Club Formula Ford, let alone anything else.

This all sounds harsh, but people need and should fact check everything and some of it is pretty easy to do.

How many people online spouting about anti-dive know that too much causes weight jacking issues? Or that too makes for a terrible handling car? Or that F1 designers have been using / playing with it with the sole purpose of controlling the aero platform since 1970?

It’s not a new concept, at all, and teams in 2022-2025 didn’t suddenly “fix” their issues by just adding more. It’s not as simple as “oh they’re running more anti-dive, why didn’t I think of that?”.

At what point did Craig suggest McLaren were running Anti dive suspension? I must have missed that because all I heard was he said some people were claiming that, implying he disagreed

[Hoffman900]

Is there a point to arguing over Craigs credentials? Over the years he has been of great benefit to Formula One technical analysis both on this very site, through his own channels, and with professional publications including appearances on sky F1. In fact here we are right now discussing his illustration

Gary Anderson used to be a technical director, but people complain about him too. Perhaps we should be in by Adrian Newey to Analyse the field, but I still suspect some would not be happy

It matters when they position themselves as experts and share misinformation (and often not on purpose) and then people on the internet just keep repeating it, without questioning it, until it becomes internet fact.

Sam Collins is another one. He has an engineering degree, has work for Race Car Engineering (the publication), but haven listen to him talk over the years, I don’t think I’d let him anywhere near a Club Formula Ford, let alone anything else.

This all sounds harsh, but people need and should fact check everything and some of it is pretty easy to do.

How many people online spouting about anti-dive know that too much causes weight jacking issues? Or that too makes for a terrible handling car? Or that F1 designers have been using / playing with it with the sole purpose of controlling the aero platform since 1970?

It’s not a new concept, at all, and teams in 2022-2025 didn’t suddenly “fix” their issues by just adding more. It’s not as simple as “oh they’re running more anti-dive, why didn’t I think of that?”.

At what point did Craig suggest McLaren were running Anti dive suspension? I must have missed that because all I heard was he said some people were claiming that, implying he disagreed

He has for the last two years as have all the F1 “technical” twitter-sphere. I guess he has to play the algorithm game.

TBF to Craig, it’s a term / point of interest for him going back to the early 20-teens.

Are you going to add anything technical to the discussion or are you going to keep going on with this?

[the EDGE]

He has for the last two years as have all the F1 “technical” twitter-sphere. I guess he has to play the algorithm game.

TBF to Craig, it’s a term / point of interest for him going back to the early 20-teens.

Are you going to add anything technical to the discussion or are you going to keep going on with this?

No.

I do not have an engineering background and neither am i involved in Motor sport. What could I possibly have to add?

[Hoffman900]

The source of all this was this post:
https://www.reddit.com/r/F1Technical/co ... &context=3

And the author positioned himself as knowing because he was involved in Formula SAE / Student. Gary correctly points out you can’t know because you need to know the CoG of the car and on a FSAE car it’s mostly a mechanical exercise, where in F1 everything is about making the aero work better, even if it is mechanically worst.

The author positioned himself as “knowing this design secret” but reality is it has been used to control the aero load in F1 since 1970 and before that even for just mechanical grip reasons. This is basic front suspension stuff. If he is college age now, those designers then would be his great grand parents age wise. It’s nothing new.

[Owen.C93]

I’ve been saying for a long time that I don’t see what antidive gives you that a stiffer heave spring doesn’t. I haven’t had a compelling answer yet.

So yes I’d agree, these geometries are almost entirely down to managing the air into the floor entry and teams are willing to give up a lot of mechanical efficiency to achieve it.

[ringo]

I think too much time discussing Scarb's backgorund and not his ideas.
He's been on this forum for years also before he became F1 celebrity. Even if he is not 100% right, he makes interesting discussions. And when he's not right, it's usually because there was not enough info and an educated guess had to be made.
As for his diagram with the tie rods passing to the front of the wheel upright, i would say it's different.
The tie rod is in the centre but it crosses back over the rear lower control arm and the outer link is actually to the rear of the upright.
This is my guess anyway.
In other words if we use Scarb's drawing, mcl39 jas the link connected in the same place on the hub as in 2024 but the rack end is in the middle as his diagram shows for 2025.

Having the tie rods reach out diagonally as Scarb's has it would need a funky steering rack to provide even motion on both left and right sides while the driver turns.

Other than the steering, even though MCL38 was the champion car, it's hard to pinpoint what features made it so good everywhere.
We may still be scratching our heads as to why MCL39 is a step ahead of the others. And not it's not flexi wings.