Mclaren Mercedes MP4-25

[Pup]

No holes drilled in the bodywork of this one. Looks like they're using an exhaust tip that bolts to the floor. I suppose they might swap that out with different shapes, perhaps testing an angled cut like Ferrari moved to?

[marcush.]

setup wheels is making the job a lot easier...and removes hassle till suspension taking a set ,preloads from stering inputs,finding true track width etc.. it pays to have a set of those for every racecar.
Is it necessary to have them round ? for ease of measuring ,and avoiding cars to roll off the pads accidentially ..(with all those people around ..you can´t believe what does happen..)

I think I've seen triangular ones used on some GT cars at a ALMS race. We've used a steel square plate for our FSAE car. I suppose the round one allows you to roll it onto a scale...Though with their pneumatic jacks and stuff I don't see why they care....

I think rolling a car around on setup wheels is quite a weird idea ..i would use my measuring tools only for measuring...but then ...what do I know.

[ringo]

No holes drilled in the bodywork of this one. Looks like they're using an exhaust tip that bolts to the floor. I suppose they might swap that out with different shapes, perhaps testing an angled cut like Ferrari moved to?

Those little pipes under the main pipe may have sensors in them. They may be measuring back pressure.
Notice the tip is a diferent material from the yellow looking part it's attatched to.
So this tip could be for testing only. Maybe if they are happy with their results, they'll run the angled cut.
I think their main problem with the angled cut pipe is the lower control arm. The pipe has to be cut in a way that the plume doesn't soak the arm with heat, though running at high speeds could provide enough cooling air for the control arm.

[bonjon1979]

Looks like this is designed to accept another piece. Some aero bits to influence the shape of the exhaust plume perhaps?

Good spot. It looks like you can see the screw holes.

[marcush.]

which parts can be changed when wet race conditions are announced?


- if the FIA technical delegate is satisfied that changes in climatic conditions necessitate alterations to the specification of a car, changes may be made to the air ducts around the front and rear brakes and radiator ducts. These changes may be made at any time after the message “CHANGE IN CLIMATIC CONDITIONS” is shown on the timing monitors, from this point the choice of brake cooling and radiator ducts is free, subject always to compliance with the relevant Technical Regulations.
- bodywork (excluding radiators) may be removed and / or cleaned ;

so in effect you could change the radiator exit duct to reroute the exhaust ,I´d say..

[kalinka]

Maybe I'm stupid, but what is that "flat black box" in front of the rear tyre is ? It seems to have no electronics or sensors inside. It sounds stupid, but my first thougth was that it's some kind of ballast weigth, and surely it seems very temporary. I never seen anything like this in this part of the car. I'm surpised that no one of you asked for it, like it's a very much stanard piece on cars ...???

[wesley123]

it is an duct which routes air to the diffusers sides(to shield it off from tire turbulence, increasing its efficiency)

[autogyro]

Could be to stop the floor flapping up and down.

[Pup]

It's a sensor. Note the silver wires leading from it back to the diffuser, and the fact that it covers the same spot that the tire temp sensor usually sits.

[Pup]

Those little pipes under the main pipe may have sensors in them.

My guess is that they are just screwed to the floor to reduce vibrations. That, and it provides an easy way to alter the exit shape if they plan to experiment. It's probably a different material because it's machined.

[feynman]

I would suggest that the "cable" from the data-collection box is in fact armored, heat resistant, air-lines leading to an array of pitot tubes, at least that's what I think I can see lurking in the shadows of this image:



More mapping of airflow for the big McLaren computer.

[ringo]

It wont reduce vibrations, it will transmit engine vibration to the floor, so i don't think it's for that purpose.
A better way to reduce vibration would be some kind of clamp with rubber bushing.

Now that i look at it a second time. It is not attached to the pipe behind it. There is a gap between the 2 pieces. The two piplets are either sensor ports and or angle adjustment struts.
So the silver coloured pipe is definitely a test piece. I would say it is a nozzle, and it's angle can be adjusted.

See the slight angle theta.

Rebull's exhaust pipes have a slight downward angle, which blasts the gases onto the floor and down and around the sides of the diffuser.

Mclaren seem to be investigating various pipe angles. Thrust Vectoring maybe

[volarchico]

I would suggest that the "cable" from the data-collection box is in fact armored, heat resistant, air-lines leading to an array of pitot tubes, at least that's what I think I can see lurking in the shadows of this image:

[IMAGE 2 POSTS ABOVE]

More mapping of airflow for the big McLaren computer.

Good catch! imightbewrong asked about that "grating" earlier, but I think you're right and it's another pitot rake.

[raymondu999]

Interesting how they're replacing their original exhaust holes with gills to help the engine breathe better, while the other teams don't see the need, or didn't think about it.
That said, their rear end is looking cleaner and their ass looking tighter, great for a cleaner airflow around. Just that bulbous engine cover is now looking fat.
Given their love of assymetrical exhausts though, are they showing any signs of using an assymetrical exhaust setup for the floor?

[thestig84]

Given their love of assymetrical exhausts though, are they showing any signs of using an assymetrical exhaust setup for the floor?

They have never had asymmetrical exhausts....just exhaust openings that were the main cooling outlets. Exhausts and cooling is now separate so exhausts will never be asymmetrical, the cooling outlets might be however.