Koenigsegg. The unloved super car?

[Bezza1969]

GALLARDOGUY said:

LongLiveTazio said:

Blind faith has no place in science.

Pagani Automobili will have done the science.

Pagani of all people would not release a car that didn't do everything at the top of its game.

You know both know that as well as I do.

For the record I actually prefer Koenigsegg's but marvel at Pagani's anal attention to every single detail.

As fun/tedious (delete as applicable) as this has been, the football's about to start, so I will leave you to it.

I think its the old italian bias and the fact that the Koenigsegg is swedish. People say the Egg has never delivered, but go back and read EVOs article from about 2002/03 on the autobahn and you will see that a perfectly fit Zonda S was unable to hit a genuine 200 MPH with Andy Wallace at the wheel!! So much for aero testing eh? Whereas the original CC8S was the second car ever that autocar managed a 0-200 MPH acceleration figure for. Dont get me wrong, I love Paganis but feel Koenigsegg dont get treated with enough respect, because they come from a country not known for super cars. And yes, until this month EVO always was very PRO Pagani. This was only the second koenigsegg feature in about 5 years!!

[Streetrod]

Bezza1969 said:

GALLARDOGUY said:

LongLiveTazio said:

Blind faith has no place in science.

Pagani Automobili will have done the science.

Pagani of all people would not release a car that didn't do everything at the top of its game.

You know both know that as well as I do.

For the record I actually prefer Koenigsegg's but marvel at Pagani's anal attention to every single detail.

As fun/tedious (delete as applicable) as this has been, the football's about to start, so I will leave you to it.

I think its the old italian bias and the fact that the Koenigsegg is swedish. People say the Egg has never delivered, but go back and read EVOs article from about 2002/03 on the autobahn and you will see that a perfectly fit Zonda S was unable to hit a genuine 200 MPH with Andy Wallace at the wheel!! So much for aero testing eh? Whereas the original CC8S was the second car ever that autocar managed a 0-200 MPH acceleration figure for. Dont get me wrong, I love Paganis but feel Koenigsegg dont get treated with enough respect, because they come from a country not known for super cars. And yes, until this month EVO always was very PRO Pagani. This was only the second koenigsegg feature in about 5 years!!

The Huayra has been tested over million kilometers with separate testing programs also run by AMG for the engine/gearbox and Bosch on the ESP system that ties into the active aero. So believe me it has been tested, check it out here: http://www.youtube.com/watch?v=lmDG6Pf4jfI

As for the Koenigsegg their recent moves on the PR front are very positive and are getting a good reactions. Watch the video series on the Drive channel, its very good

[vincegail]

I was very envious with the very young testdriver of Koenigsegg. Must be one of the coolest jobs to have!

[Tom73]

Streetrod said:

Hello Tom, back again I see defending the flag, good on you mate. Look if you read through this thread I think you find that the general consensus is that if we had the money many on here would be beating a path to Koenigseggs door. Most realize now what the company has much too offer now that they are making a much more positive effort on the PR front. The recent Drive channel videos are highlighting their tech and they are also now contributing to treads over on Teamspeed and seem more that willing to answer questions directly which is great. So don’t feel the need to fight their battles, they seem more that capable of doing it themselves.

As for the introduction of Pagani into threads about Egg's why does this upset you so much? Both companies occupy the same space and chase the same customers so it’s obvious that any conversation about one is likely to include a references about the other. Don’t slam Pagani fanboyisim when you are just as much a Koenigsegg fanboy yourself. Both companies are now doing great things and this should be celebrated

As for taste, yes Pagani have built some questionable cars but even you have to admit that the Purple Egg complete with gold interior is pushing it a bit for western eyes. If you are Chinese by the way I apologise if I am calling your taste into question, it all comes down to cultural differences in the end.

So lighten up mate.

Sigh. I don't even..............

Streetrod said:

Oh by the way the last time we conversed you questioned the dynamic ability of the Huayra and its moveable aerodynamic aids. Having now seen the lap time at the Top Gear track do you still stand by those comments?

Oh I'm pleased they incorporated some of the changes I was screaming for. Or at least that they did in the review car. Like this after market looking front splitter and I assume slightly different undertray as well.



Thankfully they didn't listen to your highly educated ideas:

http://www.pistonheads.com/gassing/topic.asp?h=8&a...

Tom73 said:

Why substitute a proper front splitter and a protruding diffuser (with INSTRUMENTAL fins) to clean and accelerate flow, for a bunch of flaps that wont work as advertised for too many reasons to mention in this post?

Streetrod said:

Now too the aero which is very misunderstood on this car. First it does not require a front splitter as the design of the nose section already acts line one and produces down force .

Tom73 said:

The nose section does not act like a proper front splitter.

Why? There's two reasons why the length of the front splitter tends to grow with the desired track capability. One, it extends the undertray and the extra length allows the flow to accelerate more. More acceleration in flow equals more venturi effect and downforce. Two, having the front splitters extend as long as possible beyond the wheels gives you better leverage and more surface area for the downforce created by the combination of the venturi effect on the bottom and the dam effect on top. Remove either the venturi effect or the dam effect and you will drastically reduce downforce.

I'm guessing these changes will be made available in all other cars as well and not just the review car? And you and I are now on the same page not that it is a necessity seeing as how Pagani has implemented the changes?


I still wish they would replace those stupid non-functional flaps for something a little more useful though. Active suspension coupled with the review car's undertray and front splitter would work much better.

And of course I wasn't overly pleased about seeing a Zonda driver die in his car with the safety concerns I raised about the poorly designed crash structure but the Pagani boys over here at PH were all quick to blame the driver and drag his corpse through the mud so let's pretend it never happened, shall we? Everything for the brand, right? Oh how mislead I was:

Tom73 said:

The design criteria of a car like the Huayra should be the same as a Formula One car. It should be able to withstand the forces of a 230 mph crash and have the appropriate compression zones to eat some of the energy. You see, carbotanium only slightly improves tension and shear over raw carbon fiber, but it does nothing to aid compression and the tensile and shear strength will be less than just about any given laminate that incorporates raw materials with better tensile and shear strength. As a substitute for carbon fiber alone it's a great material but as a all in one material it's not very good. This is why in the racing and aero industry you laminate carbon fiber with other materials like divinycell, kevlar, polymer or aluminium honeycomb; to get the whole spectrum of tension, shear and compression. You don't do one or the other, you combine them depending on what the structure requires.

This is also why a properly engineered monocoque has non tensile fracture zones where the engine and the front connects with the monocoque. At a high energy impact you want the tension and shear strength to be balanced in such a way that those bits tear off the monocoque so that when it smashes into, say a wall, it only carries the weight and energy of the cockpit. If a supercar has a high energy impact and it doesn't split in two then it's poorly engineered. And watching some of the crash photos of Paganis it's amazing that no one has got seriously hurt yet.

It should look like this

or this

and not like this


(Why do the subframe bend before tearing off?? How come anything in front or behind the cockpit is not disintegrated into small pieces when the forces going through the monocoque are great enough to completely obliterate the subframe? Should a 62 mph crash like the one in the second picture eat away at the all carbon fiber monocoque and almost expose the passanger? Is "impending death" a design criteria?)

As far as the lap time itself it's mostly about the tyres. Right now Pirelli is king and it shouldn't come as a surprise to you since you're currently being lectured over Teamspeed.

http://teamspeed.com/forums/supercars/78235-pagani...

I wouldn't expect anything less than a honest debate from you so I'm a bit surprised you didn't bring it up. Perhaps you forgot - again?

LongLiveTazio said:

I have an untrained eye to lots of things but it isn't just me who's seen plenty of videos about the Huayra to think that the flaps looked slow to respond and notice that it is very different to what other manufacturers with vastly more race and engineering experience have preferred. So until I see evidence of the contrary (beyond airbrake) I will treat it with healthy cynicism, which doesn't seem to me to be unreasonable.

Trust your eyes and common sense, I say... There is really no good way of bettering downforce than with the venturi effect or a proper wing since it's much easier to create lift with a change in flow speed to cause changes in pressure than to simply use the relatively meager dam effect of the Huayra's flaps. This is why the early airplane models of flapping, flat, bird like wings didn't work as well as a proper airfoil. Or why airplanes aren't designed like kites. Whether we're talking wings, the undertray of a race car, a jet engine or something as trivial as a alcohol stove they all use the same principle so it's fairly tried and tested (dry sarcasm). Like I said before in my debate with streetrod linked earlier in this post there are no actual guarantees that the flaps would work as they cause a change in flow. In theory they could actually create a net lift if they slow down the flow too much or create a wake turbulence. There's a reason why aero engineers don't put the flaps at the front of the airfoil/wings and it's not because it's too damn good of a concept for the aero industry. The parameters alone to make it work in theory are mind-boggling and Pagani is not McDonnell Douglas et al.

The question then is why they went through all this trouble of creating non effective flaps to create dam pressure with a potential net lift when they could have used active suspension to optimize roll/contact surface and the venturi effect of the undertray? I'm sure they're fantastic airbrakes and are more than useful in this regard, but to go from that to telling us that this





is a more useful and "innovative" concept than the principles (Bernoulli's principle) of these





... now that's just downright insulting. Someone over at Pagani must've skipped a class or they're consciously being dishonest.

Streetrod said:

The Huayra has been tested over million kilometers with separate testing programs also run by AMG for the engine/gearbox and Bosch on the ESP system that ties into the active aero. So believe me it has been tested, check it out here: http://www.youtube.com/watch?v=lmDG6Pf4jfI

It would take them 5 years of 8 hours of continous driving each day at an average 70 km/h to reach 1000000 km. Up until not so long ago there was only the one test mule so you do the math. Surely there's some classic Pagani trickery in there.

Also I'm not sure how highly it speaks of the brand if they need 1000000+ km before they figure out it might be a good idea to add a front splitter.

[Tom73]

The Ultimate Test Drive - Inside Koenigsegg

http://www.youtube.com/watch?v=nblIoM7zbwI

[dom9]

Tom73 - What a post!

As a former aero guy, by education and in a previous career... I can't see how the flaps would really make a positive difference.

And yes, plenty of F1 teams and Aircraft manufacturers make a total balls-up of aero, which costs them $100M's...

Pagani do not have the resources of these people and it's an incredibly complex field; control in aerodynamics.

CFD isn't really up to modelling this in the real world. Are there any windtunnels that can handle it, and have been used?

You could use a scale model but scaling the results is hard, especially with flow fields that are changing so quickly and dramatically.

I like both Paganis and 'eggs - I'll may never be able to afford one but, yes, I would prefer the 'egg. It just looks better and feels, somehow, purer, now.

But, I am no fanboy - I just find a lot of this 'active' and 'aero' talk as complete nonsense and gimmickery.

Keep the bodywork nice and tight to the mechanics, even if you have to compromise the mechanics a little, keep the floor flat and add a splitter, diffuser and wing where necessary.

Why don't we have active aero in motorsports, really? Because it would cost ridiculous amounts to successfully develop and those amounts are way beyond the depths of HP's pocket.

[Tom73]

dom9 said:

Tom73 - What a post!

As a former aero guy, by education and in a previous career... I can't see how the flaps would really make a positive difference.

And yes, plenty of F1 teams and Aircraft manufacturers make a total balls-up of aero, which costs them $100M's...

Pagani do not have the resources of these people and it's an incredibly complex field; control in aerodynamics.

CFD isn't really up to modelling this in the real world. Are there any windtunnels that can handle it, and have been used?

You could use a scale model but scaling the results is hard, especially with flow fields that are changing so quickly and dramatically.

I like both Paganis and 'eggs - I'll may never be able to afford one but, yes, I would prefer the 'egg. It just looks better and feels, somehow, purer, now.

But, I am no fanboy - I just find a lot of this 'active' and 'aero' talk as complete nonsense and gimmickery.

Keep the bodywork nice and tight to the mechanics, even if you have to compromise the mechanics a little, keep the floor flat and add a splitter, diffuser and wing where necessary.

Why don't we have active aero in motorsports, really? Because it would cost ridiculous amounts to successfully develop and those amounts are way beyond the depths of HP's pocket.

Bang-on, mate!

Yes if you ask me, then ideally, every performance hypercar should be shaped like the old school Le Mans cars like the Porsche 962 because it's an optimized street style shape that stayed competitive all the way from the Porsche 917 in the early 70's to the Dauer 962 in the mid 90's until aeros got out of hand and the Le Mans cars began looking more like F1 cars in the hunt of eliminating frontal area. It's a clean, simple body that works like a canvas to which you can add the desired aerodynamics; much like the fuselage of a plane. There's really no need to make it much more complicated than that from a pure performance perspective unless it's consciously done to remove frontal area (like air channels for instance). There's been a ton of manufacturers who gets this simple concept of aero design, not just Koenigsegg. Pagani? I suppose they're trying. In fairness to them though you can't fault them for catering to the market when it's comprised of a bunch of less than educated journos and customers asking for something "not so dated" as say the XJR-15. The market simply do not comprehend that some things are timeless for a reason and best left alone if you value functionality and see that functionally as a part of the aesthetics of a performance vehicle.

dom9 said:

You could use a scale model but scaling the results is hard, especially with flow fields that are changing so quickly and dramatically.

I'm curious what this would look like since you're not only dealing with changing flow fields but the behavior of the suspension as well. Even if they did find a somewhat useful pseudo dynamic model it would go out the window as soon as you added the dynamic mechanical parameters of the suspension. This is so much easier to control when you keep the parameters away and clear of the body.

F1 teams were (before it got banned) therefor much more interested in active suspension since you have a static model and mechanical properties in the suspension to keep it as static and predictable as possible beyond the confines of the test setting. In the world outside the Pagani think tank you don't solve the aerodynamic problem by adding more parameters but as you say by removing as much of them as they possibly can. They're literally working in the direct opposite direction everyone else is taking to solve the problem of dynamic flow. It's like watching some throw gasoline on a fire to kill it. As if the whole village is passing buckets of water and here comes the village idiot with a bucket of gasoline...


The sensation I'm left with when looking at the Huayra's aeros is someone should have just knocked Horacio on the shoulder and told him "Maestro. Es a car-a, not a plane-a. No work-a as-a you intended", but I get the feeling that the designers are running wild over there and I'm not sure Horacio is the man to put a stop to it. For all the great work he's done in composites people forget that it was primarily for mockups and show cars. It's telling that Pagani's side ventures are design based and Koenigsegg's are engineering based.

Edited by Tom73 on Thursday 7th February 23:58

[firemanSimon]

Tom73 said:

Streetrod said:

Hello Tom, back again I see defending the flag, good on you mate. Look if you read through this thread I think you find that the general consensus is that if we had the money many on here would be beating a path to Koenigseggs door. Most realize now what the company has much too offer now that they are making a much more positive effort on the PR front. The recent Drive channel videos are highlighting their tech and they are also now contributing to treads over on Teamspeed and seem more that willing to answer questions directly which is great. So don’t feel the need to fight their battles, they seem more that capable of doing it themselves.

As for the introduction of Pagani into threads about Egg's why does this upset you so much? Both companies occupy the same space and chase the same customers so it’s obvious that any conversation about one is likely to include a references about the other. Don’t slam Pagani fanboyisim when you are just as much a Koenigsegg fanboy yourself. Both companies are now doing great things and this should be celebrated

As for taste, yes Pagani have built some questionable cars but even you have to admit that the Purple Egg complete with gold interior is pushing it a bit for western eyes. If you are Chinese by the way I apologise if I am calling your taste into question, it all comes down to cultural differences in the end.

So lighten up mate.

Sigh. I don't even..............

Streetrod said:

Oh by the way the last time we conversed you questioned the dynamic ability of the Huayra and its moveable aerodynamic aids. Having now seen the lap time at the Top Gear track do you still stand by those comments?

Oh I'm pleased they incorporated some of the changes I was screaming for. Or at least that they did in the review car. Like this after market looking front splitter and I assume slightly different undertray as well.



Thankfully they didn't listen to your highly educated ideas:

http://www.pistonheads.com/gassing/topic.asp?h=8&a...

Tom73 said:

Why substitute a proper front splitter and a protruding diffuser (with INSTRUMENTAL fins) to clean and accelerate flow, for a bunch of flaps that wont work as advertised for too many reasons to mention in this post?

Streetrod said:

Now too the aero which is very misunderstood on this car. First it does not require a front splitter as the design of the nose section already acts line one and produces down force .

Tom73 said:

The nose section does not act like a proper front splitter.

Why? There's two reasons why the length of the front splitter tends to grow with the desired track capability. One, it extends the undertray and the extra length allows the flow to accelerate more. More acceleration in flow equals more venturi effect and downforce. Two, having the front splitters extend as long as possible beyond the wheels gives you better leverage and more surface area for the downforce created by the combination of the venturi effect on the bottom and the dam effect on top. Remove either the venturi effect or the dam effect and you will drastically reduce downforce.

I'm guessing these changes will be made available in all other cars as well and not just the review car? And you and I are now on the same page not that it is a necessity seeing as how Pagani has implemented the changes?


I still wish they would replace those stupid non-functional flaps for something a little more useful though. Active suspension coupled with the review car's undertray and front splitter would work much better.

And of course I wasn't overly pleased about seeing a Zonda driver die in his car with the safety concerns I raised about the poorly designed crash structure but the Pagani boys over here at PH were all quick to blame the driver and drag his corpse through the mud so let's pretend it never happened, shall we? Everything for the brand, right? Oh how mislead I was:

Tom73 said:

The design criteria of a car like the Huayra should be the same as a Formula One car. It should be able to withstand the forces of a 230 mph crash and have the appropriate compression zones to eat some of the energy. You see, carbotanium only slightly improves tension and shear over raw carbon fiber, but it does nothing to aid compression and the tensile and shear strength will be less than just about any given laminate that incorporates raw materials with better tensile and shear strength. As a substitute for carbon fiber alone it's a great material but as a all in one material it's not very good. This is why in the racing and aero industry you laminate carbon fiber with other materials like divinycell, kevlar, polymer or aluminium honeycomb; to get the whole spectrum of tension, shear and compression. You don't do one or the other, you combine them depending on what the structure requires.

This is also why a properly engineered monocoque has non tensile fracture zones where the engine and the front connects with the monocoque. At a high energy impact you want the tension and shear strength to be balanced in such a way that those bits tear off the monocoque so that when it smashes into, say a wall, it only carries the weight and energy of the cockpit. If a supercar has a high energy impact and it doesn't split in two then it's poorly engineered. And watching some of the crash photos of Paganis it's amazing that no one has got seriously hurt yet.

It should look like this

or this

and not like this


(Why do the subframe bend before tearing off?? How come anything in front or behind the cockpit is not disintegrated into small pieces when the forces going through the monocoque are great enough to completely obliterate the subframe? Should a 62 mph crash like the one in the second picture eat away at the all carbon fiber monocoque and almost expose the passanger? Is "impending death" a design criteria?)

As far as the lap time itself it's mostly about the tyres. Right now Pirelli is king and it shouldn't come as a surprise to you since you're currently being lectured over Teamspeed.

http://teamspeed.com/forums/supercars/78235-pagani...

I wouldn't expect anything less than a honest debate from you so I'm a bit surprised you didn't bring it up. Perhaps you forgot - again?

LongLiveTazio said:

I have an untrained eye to lots of things but it isn't just me who's seen plenty of videos about the Huayra to think that the flaps looked slow to respond and notice that it is very different to what other manufacturers with vastly more race and engineering experience have preferred. So until I see evidence of the contrary (beyond airbrake) I will treat it with healthy cynicism, which doesn't seem to me to be unreasonable.

Trust your eyes and common sense, I say... There is really no good way of bettering downforce than with the venturi effect or a proper wing since it's much easier to create lift with a change in flow speed to cause changes in pressure than to simply use the relatively meager dam effect of the Huayra's flaps. This is why the early airplane models of flapping, flat, bird like wings didn't work as well as a proper airfoil. Or why airplanes aren't designed like kites. Whether we're talking wings, the undertray of a race car, a jet engine or something as trivial as a alcohol stove they all use the same principle so it's fairly tried and tested (dry sarcasm). Like I said before in my debate with streetrod linked earlier in this post there are no actual guarantees that the flaps would work as they cause a change in flow. In theory they could actually create a net lift if they slow down the flow too much or create a wake turbulence. There's a reason why aero engineers don't put the flaps at the front of the airfoil/wings and it's not because it's too damn good of a concept for the aero industry. The parameters alone to make it work in theory are mind-boggling and Pagani is not McDonnell Douglas et al.

The question then is why they went through all this trouble of creating non effective flaps to create dam pressure with a potential net lift when they could have used active suspension to optimize roll/contact surface and the venturi effect of the undertray? I'm sure they're fantastic airbrakes and are more than useful in this regard, but to go from that to telling us that this





is a more useful and "innovative" concept than the principles (Bernoulli's principle) of these





... now that's just downright insulting. Someone over at Pagani must've skipped a class or they're consciously being dishonest.

Streetrod said:

The Huayra has been tested over million kilometers with separate testing programs also run by AMG for the engine/gearbox and Bosch on the ESP system that ties into the active aero. So believe me it has been tested, check it out here: http://www.youtube.com/watch?v=lmDG6Pf4jfI

It would take them 5 years of 8 hours of continous driving each day at an average 70 km/h to reach 1000000 km. Up until not so long ago there was only the one test mule so you do the math. Surely there's some classic Pagani trickery in there.

Also I'm not sure how highly it speaks of the brand if they need 1000000+ km before they figure out it might be a good idea to add a front splitter.

ok.... what he said

[Streetrod]

Tom I wish we could have a conversation with it always becoming so adversarial. If we are going to disagree on a subject then so be it, but there is no need to be aggressive, so can we both put that behind us now and move on.

Right, I have no issue with your general arguments about aerodynamics, the science backs you up. The adding of the splitter to the Huayra is part of an optional track pack which does not include any changes to the cars undertray which is essentially flat until it gets to the rear diffuser. The Huayra runs on a longer wheelbase than the Zonda wheelbase so with a longer under tray produces higher down forces, which is basic aerodynamics 101.

So what other factors have contributed to its amazing lap times. Well lets checkout its suspension, encase you did not know the Huayra suspension is directly lifted from the Zonda R, the current outright record holder on the TG track. The only difference is that the Huayra has more road compliant bushings. Although not totally active the Pagani's front suspension does raise its self under braking to maintain its attitude. Do these factors contribute to its speed? I think so

You mention the tyres, which I did comment on over on Teamspeed by the way, as being the main contributor to the lap times, if we were talking a few tenths here or there then I would be happy to agree with you, but when your are talking about nearly three seconds faster than a 4WD Aventador (Similar power, less torque) over a relatively short track then surely you must admit something more than just the compound on the street tyres is contributing to its pace. Plus if we flag up tyres as being the only reason one car is faster than another then we might as well disregard all tests from now on unless a control tyre is introduced and all cars must be forced to use it to create a level playing field, which we all know is frankly silly.

In a street car especially its performance cannot be laid at the door of any one thing, these cars are very much a sum of their parts and design.

Now too another point, you said this: "And of course I wasn't overly pleased about seeing a Zonda driver die in his car with the safety concerns I raised about the poorly designed crash structure but the Pagani boys over here at PH were all quick to blame the driver and drag his corpse through the mud so let's pretend it never happened, shall we? Everything for the brand, right? Oh how mislead I was:

The crash structures in both the Zonda and the Huayra, have both passed all the tests required with flying colours with singular cars being strong enough to survive multiply crash tests, how much stronger do you expect them to be? As for the guy that died mentioned above, we all know he did not die in the car, he was thrown out because he was not wearing a seat belt and died on the street from the impart injuries he sustained there, not in the car. His passenger who was wearing his belt walked away with no injuries. Would you therefore be happy to withdraw your above statement?

Tom you also said this:"It would take them 5 years of 8 hours of continuous driving each day at an average 70 km/h to reach 1000000 km. Up until not so long ago there was only the one test mule so you do the math. Surely there's some classic Pagani trickery in there. Sorry mate but I'm afraid you are wrong here again, there are were actually five test mules the last time I looked, there would have been six but one was crashed in a high speed test in South Africa. In fact AMG employ more people on the Huayra engine test and production team than Pagani employ themselves.

Having spoken to the Koenigsegg boys over on Teamspeed it appears they are not going to challenge to Pagani’s times anytime soon. Can we read anything into this, its best not to speculate I suppose. The game is changing rapidly at the moment. The Venom GT has already taken the Koenigsegg 0-300 kph record and I suspect the Pagani’s record will be lucky to last until the summer once the McLaren P1 and F150 hit the track. One thing we can guarantee is that this year is going to be very interesting

[isaldiri]

dom9 said:

Tom73 - What a post!

As a former aero guy, by education and in a previous career... I can't see how the flaps would really make a positive difference.

And yes, plenty of F1 teams and Aircraft manufacturers make a total balls-up of aero, which costs them $100M's...

Pagani do not have the resources of these people and it's an incredibly complex field; control in aerodynamics.

CFD isn't really up to modelling this in the real world. Are there any windtunnels that can handle it, and have been used?

You could use a scale model but scaling the results is hard, especially with flow fields that are changing so quickly and dramatically.

I like both Paganis and 'eggs - I'll may never be able to afford one but, yes, I would prefer the 'egg. It just looks better and feels, somehow, purer, now.

But, I am no fanboy - I just find a lot of this 'active' and 'aero' talk as complete nonsense and gimmickery.

Keep the bodywork nice and tight to the mechanics, even if you have to compromise the mechanics a little, keep the floor flat and add a splitter, diffuser and wing where necessary.

Why don't we have active aero in motorsports, really? Because it would cost ridiculous amounts to successfully develop and those amounts are way beyond the depths of HP's pocket.

Could I drop a question at yourself and Tom by the way.... I have always wondered, why haven't more sportscar manufacturers used underfloor fans to increase the downforce of their cars? The only car I can think of that uses that is Mclaren F1 and I am quite surprised no one else has tried to do something similar.

[dom9]

isaldiri said:

Could I drop a question at yourself and Tom by the way.... I have always wondered, why haven't more sportscar manufacturers used underfloor fans to increase the downforce of their cars? The only car I can think of that uses that is Mclaren F1 and I am quite surprised no one else has tried to do something similar.

I don't think the McLaren F1 uses it in quite the same way as Gordon Murray did on the Brabham Fan Car, for example. There has been a lot of testing done of blowing and sucking wings to affect downforce/ drag/ boundary layer to effectively improve inefficiency and I had a feeling that was how it was used in the F1, as opposed to sucking it to the floor i.e. it improved the efficiency of some of the surfaces to ensure downforce as opposed to lift, have more angle of attack before stall, reduce drag etc.

My Mac F1 book is back in the UK (I am working in the US at the moment) and probably in storage, so I'd have to look at the pictures again to see how it worked but I remember some sketches with blue and red arrows through fans for the air flow.

I think the problem with your average road/ sports car is that they simply do not need to produce downforce, you just don't want enormous amounts of lift, specifically at one end or the other. Some other thoughts off the top of my head:

- Why add electric fans to a car when they are likely heavy and expensive, perhaps fail easily?
- Engine driven fans would be difficult on a front-engine car to duct (better on Mid engine, see next point).
- Fans that produce significant suction under the car would be chucking a huge amount of dirt/ debris out the back i.e. at other cars.
- Group C/ Le Mans style cars didn't need fans to produce lift/drag ratios high enough to cause drivers to pass out (before scaling them back).
- Road cars need significant ride-height, which means any under-car suction loses its effectiveness, rapidly.
- Why do you need that much downforce - it would be parastic on the engine etc (but you could have it on a clutch).

Certainly there are some surfaces on supercars that could be blown/ sucked for better efficiency and their price and the small gains they are going for may justify the cost but I don't see a need for them on 99.9% of road cars or even sportscars.

When I was working at Lotus, they were testing a car in a wind tunnel and had also take a Porsche 911 (I forgot which variant) and a Ferrari F360, amongst others, in there and compared results from a full scale test. Now, most of those tunnels lie in all honesty, as they are just too small for a full size car, BUT what they did find was that even cars that are said to produce downforce still produce lift and it doesn't materialise in reality.

Yet journos all talk about feeling the downforce at speed and the aero working, but unless they test it back-to-back with the same car without the aero bits, they don't know. They really don't. And who is to say, at road speed, it isn't the new suspension setup?

I was going to write more in my previous reply about Active Suspension being probably a better way forward than active aero, especially for a road car and Lotus had really made some good headway with that and had it on a test Esprit, which was very fast, before a lot of that stuff got canned by the FIA etc. But that was a long time ago and many of the guys with the lessons learned have probably gone!

Good discussion, guys!

[isaldiri]

dom9 said:

I don't think the McLaren F1 uses it in quite the same way as Gordon Murray did on the Brabham Fan Car, for example. There has been a lot of testing done of blowing and sucking wings to affect downforce/ drag/ boundary layer to effectively improve inefficiency and I had a feeling that was how it was used in the F1, as opposed to sucking it to the floor i.e. it improved the efficiency of some of the surfaces to ensure downforce as opposed to lift, have more angle of attack before stall, reduce drag etc.

My Mac F1 book is back in the UK (I am working in the US at the moment) and probably in storage, so I'd have to look at the pictures again to see how it worked but I remember some sketches with blue and red arrows through fans for the air flow.

I think the problem with your average road/ sports car is that they simply do not need to produce downforce, you just don't want enormous amounts of lift, specifically at one end or the other. Some other thoughts off the top of my head:

- Why add electric fans to a car when they are likely heavy and expensive, perhaps fail easily?
- Engine driven fans would be difficult on a front-engine car to duct (better on Mid engine, see next point).
- Fans that produce significant suction under the car would be chucking a huge amount of dirt/ debris out the back i.e. at other cars.
- Group C/ Le Mans style cars didn't need fans to produce lift/drag ratios high enough to cause drivers to pass out (before scaling them back).
- Road cars need significant ride-height, which means any under-car suction loses its effectiveness, rapidly.
- Why do you need that much downforce - it would be parastic on the engine etc (but you could have it on a clutch).

Certainly there are some surfaces on supercars that could be blown/ sucked for better efficiency and their price and the small gains they are going for may justify the cost but I don't see a need for them on 99.9% of road cars or even sportscars.

When I was working at Lotus, they were testing a car in a wind tunnel and had also take a Porsche 911 (I forgot which variant) and a Ferrari F360, amongst others, in there and compared results from a full scale test. Now, most of those tunnels lie in all honesty, as they are just too small for a full size car, BUT what they did find was that even cars that are said to produce downforce still produce lift and it doesn't materialise in reality.

Yet journos all talk about feeling the downforce at speed and the aero working, but unless they test it back-to-back with the same car without the aero bits, they don't know. They really don't. And who is to say, at road speed, it isn't the new suspension setup?

I was going to write more in my previous reply about Active Suspension being probably a better way forward than active aero, especially for a road car and Lotus had really made some good headway with that and had it on a test Esprit, which was very fast, before a lot of that stuff got canned by the FIA etc. But that was a long time ago and many of the guys with the lessons learned have probably gone!

Good discussion, guys!

Much appreciated for your reply, highly interesting and very comprehensive . You've made me dig up my copy of Driving Ambition to have another look and as you said, the fans were indeed used to control the centre of pressure/boundary layer than for pure downforce generation.

[Tom73]

isaldiri said:

Could I drop a question at yourself and Tom by the way.... I have always wondered, why haven't more sportscar manufacturers used underfloor fans to increase the downforce of their cars? The only car I can think of that uses that is Mclaren F1 and I am quite surprised no one else has tried to do something similar.

No need to mirror dom's brilliant post. To add something to it the way they did it on the Brabham is very cumbersome and it would have to be scaled accordingly to the increased air volume of the ride height and surface area of a street car. For just cleaning airflow with smaller fans there's better methods like vortex generating side skirts that creates a barrier of low pressure vortices that functions like the old low hanging rubber side skirts on the early ground effect F1 cars.

Also you can create much more downforce with body and undertray aerodynamics than with fans. If you take a B52 for instance then it would require massive rotors to have the body function as a helicopter with full load which is the difference between a fan car and a car with modern use of aerodynamics. Fans are relatively not very efficient as you can imagine.



Quick note about the downsides of airfoils. Body airfoils create a lot of drag and they're compared to an undertray relatively small surfaces for creating downforce. The drag can be offset by aeroelastic or hydraulic adaptive wings (NOT flaps) but you can only do so much with the surface area in a street car that doesn't have the weight or the intricate body and wings of a F1 car. Most of the gain in F1 cars is in fact that the body itself doesn't create much lift to counteract the downforce from the wings. The less aerodynamic and slick the body of the car is the more downforce you'll need just to cancel out it's lift.

Undertray aerodynamics or ground effect is where it's at. It's the lowest possible downforce to drag coefficient as it doesn't come with the penalty of the dam effect and turbulence of many small wings and you can essentially turn the whole car into one big inverted wing. The reason why manufacturers don't do this to it's full extent as of now is because it's sensitive to pitch, roll and heave and if you're exploiting the limits of it and say hit a bump you are way past the safety margins of the tyres and suspension - this is why it's heavily restricted in F1. Even with todays moderate venturi effect a car going through a corner will have downforce that's not a linear curve but a series of peaks and valleys and manufacturers will seek to have the valleys within the safety margins of everything else. It's usually only there to cancel out the body's lift + a few kilos to keep it neutral with mechanical grip and then they add the bulk of the positive downforce via wings and body aero.

The fix to this problem is active suspension to ensure that you wont suddenly lose downforce when you're past the limit. Keep in mind that going through the corner at 5G with largely undertray downforce would be the equivalent of flying through it with a airplane a few inches off the ground so it takes a different level of control to make it work. When guys were dropping like flies in F1 from the 70's to the early 80's this was the main culprit.

You could also add active suspension without exploring the limits of undertray aero. This is what they did in the Williams FW14B-FW15C under F1s strict ground effect restrictions and it gave them a couple of seconds per lap just by eliminating the valleys of the downforce curve and making it more linear and predictable; they did not actually use it to add more ground effect because they weren't allowed to. And this was also with yesterdays laser tech and computer power.



The third route is to make it more linear using the engine to blow the diffusers. This is particularly useful during throttle and will mainly help to balance out a downforce drop when the car is exiting a corner and returning to center roll and from the squat created when the anti-roll bars lowers the ride height in the roll. There's a couple of different variants that's been used and banned in F1 and both of them work by cleaning turbulent flow from the diffusers to linearly amp flow and creating more downforce with throttle input. Koenigsegg uses a variant of this in the MY2013 exhaust that adds a little downforce but more importantly should add stability to the already existing venturi effect by acting like a engine powered center tunnel of sorts. This would be an example of a nifty low "cost" fix that any hypercar manufacturer can do.

http://www.youtube.com/watch?v=laQz0Ih4u0U


To summarize then the evolution of aerodynamics in terms of what the makers can do would look like this.

1) An aerodynamically slick body and good venting to eliminate buffering and lift.
2) Bigger wings and more intricate body airfoils.
3) Diffusers to add venturi effect.
4) Aeroelastic or hydraulic adaptive wings to eliminate drag in body airfoils.
5) Stiffer anti-roll bars with heave springs, better progressive dampers, blown diffusers, vortex generating side skirts, anti-dive systems/splitter cut outs, camber optimized diffusers, traction/stability control and ABS - to add more stability to the venturi effect and raise the safety margins of the mechanical grip to align it with the undertray-created downforce at a higher level.
6) Low to medium responsive active suspension to optimize venturi and ground effect even further.
7) High responsive active suspension to add complete stability and push the cars beyond it's limits with undertray aero.


Koenigsegg has ticked the boxed on all things under "5" with the Agera. The CCX was at a "4". Pagani has ticked progressive dampers, anti-dive system and ABS at "5", it's at "4.5" if you will (not sure if the side skirts generates vortexes) and it's a step back from the Zonda and the Zonda R in a number of areas. The Mclaren F1 was at a "4". The McLaren P1 could be the first to tick "6.5" or "7" but it could also prove to be a complete disaster that ends up killing people - it all depends on how far their technology has come along and how far they push the boundaries.

Flaps are not included for a reason and it's because they counteract "1", does not function as "2", does nothing for "4" since the downforce is negligent compared to the drag, and there are much better ways to do "5" like ABS, anti-roll bars and progressive dampers; all of which it already has. To put it mildy it's not the best solution ever created and except the small effect it has on braking it's a 100% for show.

Edited by Tom73 on Tuesday 12th February 22:58

[Tom73]

Inside the Brain of a Swedish Bombshell - Inside Koenigsegg

http://www.youtube.com/watch?v=EvHDdNzqdTs


Chris Harris didn't like the Agera's "engineering integrity". He's obviously an expert in this area...

[Greg_D]

Tom73 said:

one hell of a post

Well i for one am not going to argue with that.

My utterly uneducated impression was that the pagani wings are largely for show and theatrics. your more knowledge based disection of the situation would appear to support that proposition.

Lets not forget that Pagani do not have engineering purity as a cornerstone of their business
can you imagine ron dennis passing a gear selection mechanism like the huayra's - 60 or 70 pieces of exquisitely machined pieces of unobtanium in order to fashion a gear selection apparatus the likes of which the world has never seen which ultimately engages a microswitch than actually changes the gear.

Don't get me wrong, i adore Pagani as much as the next person, but don't for a second think that they are at the bleeding edge of anything, they aren't... they drape a few 'technical' trinkets off their car to gain credibility, but the real reason their customers buy their cars is for the spectacle that they create and the way that they sound and drive as a basic function of their tyres, weight, power and brakes

[isaldiri]

Tom73 said:

some amazing stuff

Edited by Tom73 on Tuesday 12th February 22:58

To reiterate on the post above, that was one hell of a post, much appreciated for taking to time to reply so comprehensively.

[k-ink]

firemanSimon said:

Carl_Docklands said:

If i spent 1m+ on a super car i would expect it painted whatever color i wanted.

bellend!

They already painted that one in Bellend Purple so you're in luck.

[Tom73]

Greg_D said:

Well i for one am not going to argue with that.

My utterly uneducated impression was that the pagani wings are largely for show and theatrics. your more knowledge based disection of the situation would appear to support that proposition.

Lets not forget that Pagani do not have engineering purity as a cornerstone of their business
can you imagine ron dennis passing a gear selection mechanism like the huayra's - 60 or 70 pieces of exquisitely machined pieces of unobtanium in order to fashion a gear selection apparatus the likes of which the world has never seen which ultimately engages a microswitch than actually changes the gear.

Don't get me wrong, i adore Pagani as much as the next person, but don't for a second think that they are at the bleeding edge of anything, they aren't... they drape a few 'technical' trinkets off their car to gain credibility, but the real reason their customers buy their cars is for the spectacle that they create and the way that they sound and drive as a basic function of their tyres, weight, power and brakes

isaldiri said:

To reiterate on the post above, that was one hell of a post, much appreciated for taking to time to reply so comprehensively.

Cheers lads! On a second look "the CCX was at a 4" should've read "the CCX was at a 3" and I should've made short mention that active suspension increases mechanical grip as well but hopefully it didn't cause too much confusion.


The "gear selection apparatus" was a quality example, Greg! In one way it's timeless automotive art... but it's also a bloody Rube Goldberg machine! Every man on the planet (surely?) loves the spectacle of a Rube Goldberg machine but it's NOT the best way of doing things. Like the flaps it's very much a Leonardo da Vinci construction so true to it's word and if you appreciate it for what it is (art) then it's not worse only different, like a wooden Moggie.




The moment it becomes ridiculous is when you have auto journos and fans claiming "the thing can actually fly". Not only are you completely missing the context of the art but you're looking kind of silly in the process.

This is no doubt the better art:

http://www.youtube.com/watch?v=qybUFnY7Y8w

But this is hands down the better science:

http://www.youtube.com/watch?v=i9sHtVzdW8Q

... and they're both fun and interesting in their own right. Know how to distinguish between the two and appreciate them for what they are. There is nothing wrong with loving a wooden Moggie, juornos/fans - but don't force your way into the conversation by telling us the wooden structure is built purposely because you are making both you and us look like damn fools.

k-ink said:

They already painted that one in Bellend Purple so you're in luck.

I laughed.


On a more serious note... as suspected the bellend purple turned out much nicer away from natural light.







I'm thinking it will look stellar in it's supposed element.





Not every part of the world is grey and dreary and suited for a thousand different shades of silver...

[k-ink]

Well this thread turned out to be an education. Great posts all round and in particular to the efforts made by Tom. I'm sure we have all learned a few things along the way so the debate was well worth it. After that I now have a greater respect for Koenigsegg.

Although I would not complain if either company hired a permanent Client Style Advisor.

[vincegail]

Tom73 said:

From which facebook page did you take those photos please?