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[f1usa]

McLaren say their exhaust system along with a major upgrade will be ready for Silverstone.

What is your opinion of McLaren running 100% exhaust blown diffuser and f-duct, the two concepts seem incompatable with each other. F-duct can reduce drag of rear wing but exhaust blown diffuser will increase down-force and can't be turned off.

[bud]

Redbull wouldn't be working on an fduct if they weren't compatable.

[Frosty]

McLaren say their exhaust system along with a major upgrade will be ready for Silverstone.

What is your opinion of McLaren running 100% exhaust blown diffuser and f-duct, the two concepts seem incompatable with each other. F-duct can reduce drag of rear wing but exhaust blown diffuser will increase down-force and can't be turned off.

Yes they are compatible I'm sure you will see Ferrari using their F-duct as well as their blown diffuser so will Red Bull if they can get theirs to work. McLaren F-duct reduces the drag on the rear wing by stalling it when the driver diverts a different airflow to the rear wing that has a different pressure causing the airflow to the rear wing to split. This is done on straights to reduce drag. In the corners the rear wing works as normal to produce maximum downforce. The blown diffuser just creates a greater airflow in the diffuser which creates more downforce because of it. Having a blown diffuser does not inherently increase drag unless you have to add additional cooling ducts to cool the compact exhaust system.
So extra downforce doesn't necessarily mean drag it's just often the side effect. When your going in a straight line downforce doesn't matter unless you are breaking so the F-Duct is activated to reduce the drag on the wing the side effect of this is a loss of downforce but it doesn't matter.

[f1usa]

Both drag and excessive down-force take HP to overcome. IMO, McLaren doesn't need as much down-force from exhaust blown diffuser as RedBull.

[Frosty]

Read a very interesting suggestion on another forum suggesting that the Red Bull blown diffuser does not produce any extra down force but is instead is used for ride height control!
So the theory goes like this you want to run the car low in qualifying but you can't because in the race you will bottom out on the straight when the car is full of fuel and the diffuser is producing the maximum down force.
Solution is that you design the diffuser so that when your car is on the straight travelling at maximum speed when the airflow into the diffuser is at it's greatest the input of the exhaust gasses causes the airflow in the diffuser to separates which in turns means there's a reduction in downforce so that the car does not ride too low!

[Frosty]

Both drag and excessive down-force take HP to overcome. IMO, McLaren doesn't need as much down-force from exhaust blown diffuser as RedBull.

In an F1 car as long as the down force doesn't increase drag then you can never have too much, If your seeing cars under steer and lock wheels then it means they need more downforce. Downforce doesn't really take any more HP to overcome unless your talking about the small of amount of extra friction between the road and the tyres. Compared to the drag produced by an F1 car the downforce is a lot smaller effect on HP required.

[f1usa]

Read a very interesting suggestion on another forum suggesting that the Red Bull blown diffuser does not produce any extra down force but is instead is used for ride height control!
So the theory goes like this you want to run the car low in qualifying but you can't because in the race you will bottom out on the straight when the car is full of fuel and the diffuser is producing the maximum down force.
Solution is that you design the diffuser so that when your car is on the straight travelling at maximum speed when the airflow into the diffuser is at it's greatest the input of the exhaust gasses causes the airflow in the diffuser to separates which in turns means there's a reduction in downforce so that the car does not ride too low!

In your previous reply you say "The blown diffuser just creates a greater airflow in the diffuser which creates more downforce because of it." I agree with that and that is my point, McLaren doesn't need all the extra downforce. Why not run the exhaust from just one cylinder per side to diffuser and let the other three exhausts exit as usual. You gain some downforce without the massive heat problems. Now in this reply you are 180 degrees on the downforce issue.

[Frosty]

Read a very interesting suggestion on another forum suggesting that the Red Bull blown diffuser does not produce any extra down force but is instead is used for ride height control!
So the theory goes like this you want to run the car low in qualifying but you can't because in the race you will bottom out on the straight when the car is full of fuel and the diffuser is producing the maximum down force.
Solution is that you design the diffuser so that when your car is on the straight travelling at maximum speed when the airflow into the diffuser is at it's greatest the input of the exhaust gasses causes the airflow in the diffuser to separates which in turns means there's a reduction in downforce so that the car does not ride too low!

In your previous reply you say "The blown diffuser just creates a greater airflow in the diffuser which creates more downforce because of it." I agree with that and that is my point, McLaren doesn't need all the extra downforce. Why not run the exhaust from just one cylinder per side to diffuser and let the other three exhausts exit as usual. You gain some downforce without the massive heat problems. Now in this reply you are 180 degrees on the downforce issue.

Firstly why wouldn't McLaren want as much downforce from the diffuser as they can get? Extra downforce without drag = lap time.

My second suggestion spoke about using the blown diffuser in a way so that maximum downforce is produced in qualifying because they could run a lower ride height which gives greater downforce. Qualifying is very important this year because further to the front you qualify the better your chances in the race.

It's a good suggestion to run the system on not all of the cylinders this would obviously help the heat issue though I do not know if you are allowed to have more than two exhausts. Another thing is that unless it's working as a method of ride height control then running on not all of cylinders will not maximise the amount of downforce that could be produced.

[Fred_C_Dobbs]

Some people obviously never have heard of the Chaparral 2J, proof that there's never enough downforce.

Now it's being reported that Rinnow also will have an exhaust-blown diffuser for the GP of Europe.

[f1ea]

Both drag and excessive down-force take HP to overcome. IMO, McLaren doesn't need as much down-force from exhaust blown diffuser as RedBull.

In an F1 car as long as the down force doesn't increase drag then you can never have too much, If your seeing cars under steer and lock wheels then it means they need more downforce. Downforce doesn't really take any more HP to overcome unless your talking about the small of amount of extra friction between the road and the tyres. Compared to the drag produced by an F1 car the downforce is a lot smaller effect on HP required.

(to Frosty)

downforce does not need much additional HP to compensate (except for some friction as Frosty said). Drag does. The diffuser does not produce much drag, because it creates downforce by having a greater flow speed underneath (more flow speed = less pressure -> downforce). As opposed to the rear wing which has both a pressure gradient AND direct downforce from its inclination angle; this is where the drag in the rear wing is produced.

[Jamie]

hopfully it dosn't work.

dodgy using a promo day as a test day also.

I hope it does

you should for one it will make it yet again more exciting and will shut those tossers up who constantly complain about F1 Not being a sport.....

[texasmr2]

Temperature gradient on the rear wing end-plates to help keep tabs on overheating issues.

lq0c962345080592.jpg

[Jamie]

Temperature gradient on the rear wing end-plates to help keep tabs on overheating issues.

lq0c962345080592.jpg

Interesting..................

[Frosty]

None of the cars with the new diffuser have caught fire yet

[f1ea]

None of the cars with the new diffuser have caught fire yet

nor melted