McLaren MP4-28 Mercedes

[sm68]

I am not convinced by all this talk of the front suspension/wing. It all reads very like the discussions for Ferrari's car last year. Every other post seemed to be along the lines of "the car will never work until they change back to a conventional suspension". Ferrari stuck with that suspension and the car came good.

The MP4-28 went like stink at the first test when the rise height was wrong. I'd guess that this points to the diffuser system not working - perhaps relating to the tires distorting and changing the airflow under braking - not easy to model in a wind tunnel.

[Crucial_Xtreme]

McLaren Canada update analysis from Gary Anderson.


via AutoSport

[Pup]

Here's a good interview with Button, where I think he reveals a good bit more about their problems than we've heard before...

http://translate.google.com/translate?s ... 72001.html

Basically, there were correlation issues and also the suspension, while better in some ways, surprised them by being worse in others. The result is they have poor traction in slow corners and also have to run the car higher than they want.

Interestingly, he says that they need to solve the problems with this year's car if they're going to make next year's work, so it seems there's some consolation in that the effort they're putting into this car isn't being completely taken from next year's development.

[Clew]

WOW....was Hamilton every lucky to bolt to Merc

[ringo]

They need to put a hack saw to the front suspension. Pullrod is not the issue, it's the A arm geometry.
Front wing is the least. The car will work how it's supposed to once the designs are good. The wings aren't desing on the limit for one angle of attack.
Fix the front suspension, then adjust the rear accordingly. For all we know they have some kind of hydraulic suspension that's a complete mess that they are trying to understand.

[godlameroso]

It's very strange that the ride problems, which seemed to have been solved on the bumpy Monaco streets, reappeared with a vengeance in Canada. I'm not sure what to make of that. According to Button, the ride was the worst it's ever been.

Actually...Monaco isn't terribly bumpy, the road itself is quite well maintained, in fact I'd say Canada was far bumpier than Monaco.

I've been there on business.

Regarding the car, I think they're having the same problem Ferrari did last year when they introduced their front pull-rod suspension. They didn't anticipate all the knock-on effects it would have, it would have been one thing to only change the front suspension but they changed far more than that. By changing so much and introducing so many additional tuning parameters it makes it difficult to single out what exactly they can do to improve things, because now they don't know if it's just the front suspension or a combination of other components. Furthermore, you can't analyze components in isolation, you have to take it in as a whole.

These are simply growing pains they have to go through. Hopefully they are thinking long term and focusing on 2014, heck I wouldn't be surprised that if results don't come in a few more races they'll just turn the rest of the year into researching components for next year's car, if they haven't already.

[Consider&Go]

It's very strange that the ride problems, which seemed to have been solved on the bumpy Monaco streets, reappeared with a vengeance in Canada. I'm not sure what to make of that. According to Button, the ride was the worst it's ever been.

Actually...Monaco isn't terribly bumpy, the road itself is quite well maintained, in fact I'd say Canada was far bumpier than Monaco.

I've been there on business.

Regarding the car, I think they're having the same problem Ferrari did last year when they introduced their front pull-rod suspension. They didn't anticipate all the knock-on effects it would have, it would have been one thing to only change the front suspension but they changed far more than that. By changing so much and introducing so many additional tuning parameters it makes it difficult to single out what exactly they can do to improve things, because now they don't know if it's just the front suspension or a combination of other components. Furthermore, you can't analyze components in isolation, you have to take it in as a whole.

These are simply growing pains they have to go through. Hopefully they are thinking long term and focusing on 2014, heck I wouldn't be surprised that if results don't come in a few more races they'll just turn the rest of the year into researching components for next year's car, if they haven't already.

None of the issues Ferrari had at the start of the year were attributed to the front pull rod. They got their exhaust concept totally wrong. The wind tunnel correlation didn't help either. Malaysia is the best example where they were able to generate heat in to the front tires miles quicker than anyone else.

[Pup]

Yeah, McLaren's problems seem to be with the rear end as well - including the suspension, if you're to believe them about traction and ride height problems.

[turbof1]

Rear suspension geometry has changed as well; they had to reposition the wishbones considerable to implement the driveshaft shroud. The front suspension has changed considerably not in the sence of push to pull rod, but more due the higher chassis, changing geometry.

Of course, Ferrari had to do that as well (driveshaft shroud), and they don't have problems at all. Perhaps the difference lies in the fact that Ferrari kept changing the suspension geometry the last few years over and over again. The database they now have must be quite large, as well as their knowledge on suspension. Mclaren kept their suspension relative the same in the years prior to this one. Sudden change was going to bring them into unknown territory.

What I find staggering is that they decided to go for a higher chassis for a single year. The benefits aren't so easy to extract, as they now have found out.

The car isn't fixable. Solving the problems probably requires a new chassis, and extensive testing. For next year I'd advise them to snope off an expert on suspension from a front running team.

[Pup]

More from Button...

"I think we do have OK downforce, but the problem for us has been the ride quality of the car.

"There is a massive amount of movement of the car which really hurts the airflow and hurts the aerodynamics. Here it shouldn't be so much of problem, except for Turn 1 [Abbey] which is going to be a little tricky for us."

http://www.autosport.com/news/report.php/id/108131

Bouncy bouncy.

[trinidefender]

More from Button...

"I think we do have OK downforce, but the problem for us has been the ride quality of the car.

"There is a massive amount of movement of the car which really hurts the airflow and hurts the aerodynamics. Here it shouldn't be so much of problem, except for Turn 1 [Abbey] which is going to be a little tricky for us."

http://www.autosport.com/news/report.php/id/108131

Bouncy bouncy.

Which seems to support the aero changes that have taken place.
- Vortex generators in place of leading edge slat on front of side pods. Less sensitive to roll and pitch change of the car.
- Exhausts placed further forward sacrificing potential peak downforce but in turn making it less sensitive.
- New front wing looks to sacrifice a little downforce in exchange for being able to work better at different angles
- The cut they made in the floor, again less sensitivity but with slight downforce lost.

Anything else I am missing?

[trinidefender]

There is a picture from Canada where you can see how high the front ride height is and how far the front of the T-tray splitter is off of the ground. This in turn is reducing the rake of the car and reducing the avaliable downforce of the car as a whole. Why is it exactly that they are running such a high front ride height?

[ringo]

It's not aero from what i understand.

[Javert]

There is a picture from Canada where you can see how high the front ride height is and how far the front of the T-tray splitter is off of the ground. This in turn is reducing the rake of the car and reducing the avaliable downforce of the car as a whole. Why is it exactly that they are running such a high front ride height?

If I understood well Button's interview, the movement of the front of the car (porpoising) is the reason. AKA front pull rod.
If they run the T-tray lower then they get higher but inconsistent downforce (because of the movement), or they damage the floor

It seems that MP4-28 initial concept was to get high downforce but they were denied to do that:
- by the porpoising AKA front pull rod, making them running front higher than desidered
- from the rear tires deforming, making their initial exhaust system ineffective, cut floor to get less but more consistent DF
- from the rear suspension (however I don't understand if they run the rear higher or lower than desidered)

[gary123]

There is a picture from Canada where you can see how high the front ride height is and how far the front of the T-tray splitter is off of the ground. This in turn is reducing the rake of the car and reducing the avaliable downforce of the car as a whole. Why is it exactly that they are running such a high front ride height?

my opinion is that the car is to bumpy! being to bumpy the T-tray touches the track a lot at certain(low) ride height and this could cause an excessive wear, and this would cause a blag flag for them in the parc ferme at the end of the race.
the problems of this car cant be resolved because they would need a brand new front sospension geometry(stil pull rod but more ferrari style)