[Iron5]

Thank you, those shots are very helpful. It has them at both the front and rear?

Yes, the first two pictures (after the picture of the rear) show the positions at the front, the last four pictures show the positions at the rear. In total, the car has four such air deflectors on the underbody.

 

[invisiblewave]

Yes, the first two pictures (after the picture of the rear) show the positions at the front, the last four pictures show the positions at the rear. In total, the car has four such air deflectors on the underbody.

Thanks. My concern about just fitting front strakes is upsetting the aero balance at high speed, although I doubt it would induce rear lift. I really don't like spoilers, and they're not easy to fit anyway on mine, and presumably a spoiler would shift the handling bias rearward anyway, which is the problem I'm trying to solve.

 

[Iron5]

Thanks. My concern about just fitting front strakes is upsetting the aero balance at high speed, although I doubt it would induce rear lift. I really don't like spoilers, and they're not easy to fit anyway on mine, and presumably a spoiler would shift the handling bias rearward anyway, which is the problem I'm trying to solve.

To be honest, I wouldn't change anything on your car. The risk of creating a wrong result with negative effects is high. I have attached the pictures of the air deflectors of my 720S below. As you can see, the 720S already has a completely different solution than its predecessor. The 720S has four deflectors at the front (two on each side) and two very small air deflectors at the rear in front of the diffuser. This tells me that these solutions have been very specifically tuned for a particular car.

 

[invisiblewave]

To be honest, I wouldn't change anything on your car. The risk of creating a wrong result with negative effects is high. I have attached the pictures of the air deflectors of my 720S below. As you can see, the 720S already has a completely different solution than its predecessor. The 720S has four deflectors at the front (two on each side) and two very small air deflectors at the rear in front of the diffuser. This tells me that these solutions have been very specifically tuned for a particular car.
View attachment 228037
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No doubt they have, but anything that removes air more rapidly from underneath is going to reduce air pressure in that area, and the alternative is to adjust in a lot of negative camber, which also has undesirable side effects. The 720 I drove on track had a completely different handling bias to mine, but I don't know whether it's because of those strakes, or because McLaren tweak out the understeer on their track cars.

 

[EMF Audio (McMedics)]

No doubt they have, but anything that removes air more rapidly from underneath is going to reduce air pressure in that area, and the alternative is to adjust in a lot of negative camber, which also has undesirable side effects. The 720 I drove on track had a completely different handling bias to mine, but I don't know whether it's because of those strakes, or because McLaren tweak out the understeer on their track cars.

It's because the 720 is nowhere near anything the same car as a 570.

 

[invisiblewave]

It's because the 720 is nowhere near anything the same car as a 570.

Please explain in terms of the handling balance.

 

[NHMclaren]

Pics... View attachment 227966
View attachment 227967

Sent you a PM...add me into the group interest!

 

[herwawan]

Count me in too!

 

[Hypurone]

Please explain in terms of the handling balance.

Primarily it is the PCC system that the Super Series have that the Sport Series doesn't. The strakes in this discussion are for airflow control under the car, primarily for downforce (controlling how it flows under the car and how smoothly/quickly it reaches the Diffuser).

 

[invisiblewave]

Primarily it is the PCC system that the Super Series have that the Sport Series doesn't. The strakes in this discussion are for airflow control under the car, primarily for downforce (controlling how it flows under the car and how smoothly/quickly it reaches the Diffuser).

Right, PCC for damping, strakes and other aero devices for downforce. I can't see how adding strakes to the sport series wouldn't help with reducing front end lift.

 

[Hypurone]

I can't see how adding strakes to the sport series wouldn't help with reducing front end lift.

The splitter is the primary for that with the front openings as secondary. The strakes don't provide any downforce, they simply "control" the airflow to keep it out of areas (brakes/wheels/wheel wells) that would ruin/decrease the downforce that everything else including the underside pans etc are producing....

I guess it could help but it makes me wonder why McLaren didn't put them on...

 

[invisiblewave]

The splitter is the primary for that with the front openings as secondary. The strakes don't provide any downforce, they simply "control" the airflow to keep it out of areas (brakes/wheels/wheel wells) that would ruin/decrease the downforce that everything else including the underside pans etc are producing....

I guess it could help but it makes me wonder why McLaren didn't put them on...

They do more than that, they direct air from the underbody out to the sides, increasing the speed of the airflow and reducing pressure, thereby providing downforce, which translates to less understeer. In the 650S underbody shots that @Iron5 posted, the front strakes are directing air outboard behind the front wheels.

 

[Hypurone]

They do more than that, they direct air from the underbody out to the sides, increasing the speed of the airflow and reducing pressure, thereby providing downforce, which translates to less understeer. In the 650S underbody shots that @Iron5 posted, the front strakes are directing air outboard behind the front wheels.

Nah, it's more to allow the "main" airflow (down the center of the car) to be less turbulent and flow more cleanly to the diffuser... The strakes take the turbulent air at the corners by the wheels and direct it back behind them out of the main center flow....

 

[invisiblewave]

Nah, it's more to allow the "main" airflow (down the center of the car) to be less turbulent and flow more cleanly to the diffuser... The strakes take the turbulent air at the corners by the wheels and direct it back behind them out of the main center flow....

Same effect. If you're cleaning up the airflow, you're making it faster.

 

[Hypurone]

Same effect. If you're cleaning up the airflow, you're making it faster.

Not denying that, but as far as ADDING downforce in and of themselves, I don't see the strakes doing that... It's more of not ruining what you already have created....

 

[invisiblewave]

Not denying that, but as far as ADDING downforce in and of themselves, I don't see the strakes doing that... It's more of not ruining what you already have created....

Same difference! Lower pressure under the car means higher downforce because you're increasing the pressure differential. It's like having a diffuser for the front wheels.

 

[cdrinkh2o]

@RRD Fallbrook CA - I think you now have 4 takers in this thread. Are you still up for making them?

 

[UncleSlow]

Playing catch up here... are the front and rear set identical? My car doesn't have them... Are the mounting holes also identical?

If that is the case, one would need two sets. I am interested, if we can organise payment from this side (PayPal?). Shipping to LA, CA address.

 

[restosud]

Playing catch up here... are the front and rear set identical? My car doesn't have them... Are the mounting holes also identical?

If that is the case, one would need two sets. I am interested, if we can organise payment from this side (PayPal?). Shipping to LA, CA address.

front and rears are different. rear harder to copy as they are shaped to fit diffuser.

 

[cdrinkh2o]

OP is MIA - last on here Jan 31 - we may be out of luck?