I got a new rear wing... And it moves!
#76
The key issue is the ability to know what aero adjustments are needed on a particular circuit. And that is where my reservations are. Unless one knows how to apply the theory correctly to a particular track, I worry that the overall effects may be more detrimental than beneficial. The technology is amazing, but I think there is a need for someone close at hand to apply the necessary algorithms to make the technology work well for the track in question...
Last edited by Robin@EPL; 01-10-2011 at 07:45 AM.
#77
Here's an iP4 pic from the Friday's wind tunnel day. The F430 is doing 175mph
There are two key points to the aero. The first is magnitude. The F430 has three downforce settings, which are driven by the front splitter. The maximum downforce is great for a pro driver, but can be hard to drive for the rest of us.
Consider this. IF the car has 0 downforce through the entire speed range, you can corner with pretty much the same grip at any speed. It's very easy to find the limit, and stay on it.
Now, take a high-downforce car. The grip will drop exponentially as a function if speed. Your grip at turn-in is the max grip you'll see in the corner. Staying on the edge of a reducing G circle is hard. The difficulty increases with the slope of the reducing g's. Ie, your grip drops faster with high downforce cars. Most non-pro's do best with mid-level downforce.
The next thing is balance. Again, the top pro's want 50 / 50 front to rear downforce balance. The mid level pro's are faster with a front downforce bias. Most of the track enthusiasts are the same.
In the end, the question of aero setup is really based on the driver, not the track. For a given ride height, we can prescribe a level of downforce and get the computer to maintain a bias across a large speed range. The aero is the same on every track (taking altitude out which applies to everyone except the Colorado guys). What does change, is corner entry, suspension loading, etc. Taking that into account, however, requires having a top NASCAR / F1 team in your paddock. . . or you could spend $500k in wind tunnel testing, and we'd program it all into your wing computer
Cheers,
Greg
Last edited by Wingman (AeroM); 01-10-2011 at 01:56 PM.
#78
[quote=Wingman (AeroM);3090595]You're spot on about the balance. There is a second order effect of corner entry (which could be interpreted as "the track) which I'll address at the end of this.
There are two key points to the aero. The first is magnitude. The F430 has three downforce settings, which are driven by the front splitter. The maximum downforce is great for a pro driver, but can be hard to drive for the rest of us.
Consider this. IF the car has 0 downforce through the entire speed range, you can corner with pretty much the same grip at any speed. It's very easy to find the limit, and stay on it.
Now, take a high-downforce car. The grip will drop exponentially as a function if speed. Your grip at turn in the max grip you'll see in the corner. Staying on the edge of a reducing G circle is hard. The difficulty increases with the slope of the reducing g's. Ie, your grip drops faster with high downforce cars. Most non-pro's do best with mid-level downforce.
The next thing is balance. Again, the top pro's want 50 / 50 front to rear downforce balance. The mid level pro's are faster with a front downforce bias. Most of the track enthusiasts are the same.
In the end, the question of aero setup is really based on the driver, not the track. For a given ride height, we can prescribe a level of downforce and get the computer to maintain a bias across a large speed range. The aero is the same on every track (taking altitude out which applies to everyone except the Colorado guys). What does change, is corner entry, suspension loading, etc. Taking that into account, however, requires having a top NASCAR / F1 team in your paddock. . . or you could spend $500k in wind tunnel testing, and we'd program it all into your wing computer
Cheers,
Greg
/quote]
Greg-
Thanks for the thorough explanation of the interplay between magnitude and balance in optimizing downforce as a function of the driver. Once you think about (particularly after reading your explanation) it really is intuitive how the grip of a high down force car falls off at lower speeds therefore making it more difficult to drive. I think a lot of us reading about downforce simply assume more is better. Now I realize that tuning the magnitude and balance of the downforce to the driver is key.
I am headed to Sebring on Wednesday for 4 days at Winterfest. My 997.2 RS has 500 miles on it and between my son and I it could have over 1000 when we are done. Looking forward to the release of the AeroMotion package for the 997.2 RS when it is available.
There are two key points to the aero. The first is magnitude. The F430 has three downforce settings, which are driven by the front splitter. The maximum downforce is great for a pro driver, but can be hard to drive for the rest of us.
Consider this. IF the car has 0 downforce through the entire speed range, you can corner with pretty much the same grip at any speed. It's very easy to find the limit, and stay on it.
Now, take a high-downforce car. The grip will drop exponentially as a function if speed. Your grip at turn in the max grip you'll see in the corner. Staying on the edge of a reducing G circle is hard. The difficulty increases with the slope of the reducing g's. Ie, your grip drops faster with high downforce cars. Most non-pro's do best with mid-level downforce.
The next thing is balance. Again, the top pro's want 50 / 50 front to rear downforce balance. The mid level pro's are faster with a front downforce bias. Most of the track enthusiasts are the same.
In the end, the question of aero setup is really based on the driver, not the track. For a given ride height, we can prescribe a level of downforce and get the computer to maintain a bias across a large speed range. The aero is the same on every track (taking altitude out which applies to everyone except the Colorado guys). What does change, is corner entry, suspension loading, etc. Taking that into account, however, requires having a top NASCAR / F1 team in your paddock. . . or you could spend $500k in wind tunnel testing, and we'd program it all into your wing computer
Cheers,
Greg
/quote]
Greg-
Thanks for the thorough explanation of the interplay between magnitude and balance in optimizing downforce as a function of the driver. Once you think about (particularly after reading your explanation) it really is intuitive how the grip of a high down force car falls off at lower speeds therefore making it more difficult to drive. I think a lot of us reading about downforce simply assume more is better. Now I realize that tuning the magnitude and balance of the downforce to the driver is key.
I am headed to Sebring on Wednesday for 4 days at Winterfest. My 997.2 RS has 500 miles on it and between my son and I it could have over 1000 when we are done. Looking forward to the release of the AeroMotion package for the 997.2 RS when it is available.
#79
Greg-
Thanks for the thorough explanation of the interplay between magnitude and balance in optimizing downforce as a function of the driver. Once you think about (particularly after reading your explanation) it really is intuitive how the grip of a high down force car falls off at lower speeds therefore making it more difficult to drive. I think a lot of us reading about downforce simply assume more is better. Now I realize that tuning the magnitude and balance of the downforce to the driver is key.
I am headed to Sebring on Wednesday for 4 days at Winterfest. My 997.2 RS has 500 miles on it and between my son and I it could have over 1000 when we are done. Looking forward to the release of the AeroMotion package for the 997.2 RS when it is available.
Thanks for the thorough explanation of the interplay between magnitude and balance in optimizing downforce as a function of the driver. Once you think about (particularly after reading your explanation) it really is intuitive how the grip of a high down force car falls off at lower speeds therefore making it more difficult to drive. I think a lot of us reading about downforce simply assume more is better. Now I realize that tuning the magnitude and balance of the downforce to the driver is key.
I am headed to Sebring on Wednesday for 4 days at Winterfest. My 997.2 RS has 500 miles on it and between my son and I it could have over 1000 when we are done. Looking forward to the release of the AeroMotion package for the 997.2 RS when it is available.
http://www.youtube.com/watch?v=edEx4nXdIlY
#80
You're spot on about the balance. There is a second order effect of corner entry (which could be interpreted as "the track") which I'll address at the end of this.
Here's an iP4 pic from the Friday's wind tunnel day. The F430 is doing 175mph
There are two key points to the aero. The first is magnitude. The F430 has three downforce settings, which are driven by the front splitter. The maximum downforce is great for a pro driver, but can be hard to drive for the rest of us.
Consider this. IF the car has 0 downforce through the entire speed range, you can corner with pretty much the same grip at any speed. It's very easy to find the limit, and stay on it.
Now, take a high-downforce car. The grip will drop exponentially as a function if speed. Your grip at turn-in is the max grip you'll see in the corner. Staying on the edge of a reducing G circle is hard. The difficulty increases with the slope of the reducing g's. Ie, your grip drops faster with high downforce cars. Most non-pro's do best with mid-level downforce.
The next thing is balance. Again, the top pro's want 50 / 50 front to rear downforce balance. The mid level pro's are faster with a front downforce bias. Most of the track enthusiasts are the same.
In the end, the question of aero setup is really based on the driver, not the track. For a given ride height, we can prescribe a level of downforce and get the computer to maintain a bias across a large speed range. The aero is the same on every track (taking altitude out which applies to everyone except the Colorado guys). What does change, is corner entry, suspension loading, etc. Taking that into account, however, requires having a top NASCAR / F1 team in your paddock. . . or you could spend $500k in wind tunnel testing, and we'd program it all into your wing computer
Cheers,
Greg
Here's an iP4 pic from the Friday's wind tunnel day. The F430 is doing 175mph
There are two key points to the aero. The first is magnitude. The F430 has three downforce settings, which are driven by the front splitter. The maximum downforce is great for a pro driver, but can be hard to drive for the rest of us.
Consider this. IF the car has 0 downforce through the entire speed range, you can corner with pretty much the same grip at any speed. It's very easy to find the limit, and stay on it.
Now, take a high-downforce car. The grip will drop exponentially as a function if speed. Your grip at turn-in is the max grip you'll see in the corner. Staying on the edge of a reducing G circle is hard. The difficulty increases with the slope of the reducing g's. Ie, your grip drops faster with high downforce cars. Most non-pro's do best with mid-level downforce.
The next thing is balance. Again, the top pro's want 50 / 50 front to rear downforce balance. The mid level pro's are faster with a front downforce bias. Most of the track enthusiasts are the same.
In the end, the question of aero setup is really based on the driver, not the track. For a given ride height, we can prescribe a level of downforce and get the computer to maintain a bias across a large speed range. The aero is the same on every track (taking altitude out which applies to everyone except the Colorado guys). What does change, is corner entry, suspension loading, etc. Taking that into account, however, requires having a top NASCAR / F1 team in your paddock. . . or you could spend $500k in wind tunnel testing, and we'd program it all into your wing computer
Cheers,
Greg
#82
No, that's the whole point. Once the algorithms are in place, the wing adjusts itself automatically. When the car is hard under braking, you have lots of aero assist. When you're at 150mph on the back straight, the wing is neutral. The wing is never reading a static "program" for a specific track, it's dynamically changing based on the current grip demands of the car... which means it'll make you go faster no matter if you're on a decreasing radius off-ramp or setting up for the Esses at VIR...
What are the algorithms based on? How do they adjust for grip in the tires? HP/Weight of the car? Do they have to be re-tuned with adjustments to the car? Does it measure slip angles?
I'm also confused at 50/50 front/rear DF because that seems very vague for the various different kinds of cars with different weight balances. And how many of the GT cars can actually match rear DF in the front? Seems like the rear in RWD race cars (which is what most are) will need more DF over the powered wheels anyways.
#83
The sections of track you initially mention are the easy ones, max DF at Braking and least on the straight, but with the variety of tracks around I don't see how one set of algorithms could fit every track. That would be to say no tuning necessary ever, and that sounds far fetched for anything on a track car.
What are the algorithms based on? How do they adjust for grip in the tires? HP/Weight of the car? Do they have to be re-tuned with adjustments to the car? Does it measure slip angles?
I'm also confused at 50/50 front/rear DF because that seems very vague for the various different kinds of cars with different weight balances. And how many of the GT cars can actually match rear DF in the front? Seems like the rear in RWD race cars (which is what most are) will need more DF over the powered wheels anyways.
What are the algorithms based on? How do they adjust for grip in the tires? HP/Weight of the car? Do they have to be re-tuned with adjustments to the car? Does it measure slip angles?
I'm also confused at 50/50 front/rear DF because that seems very vague for the various different kinds of cars with different weight balances. And how many of the GT cars can actually match rear DF in the front? Seems like the rear in RWD race cars (which is what most are) will need more DF over the powered wheels anyways.
Guess what they are saying is that as you rightly put, things should be more complicated if you want perfect aerodynamics for a specific car with specific driver on a specific track.
But without the ability to spend monumental amounts of money in a wind tunnel, they provide a "generic" algorithm for a particular model of car and an "average" driver and suggest that the algorithm may not be perfect but its better than a static wing....
#85
For this reason, the GT3 Static wings will come out first. They are simple to engineer, and provide much needed rear end stability for the GT3's. It essentially functions a lot like the European 996 GT3 RS. Here's the 996 GT3 wing in development. The wing will be available in 65" and 57" span. The first one is going to VIR in a month. The wings will be released in 4 weeks.
The wings will bolt to the factory 996 GT3 uprights, as seen in the solid model after the RS.
In the active department, the turbo wings are coming out first. The moving wing on the turbo would be very difficult for Porsche to re-engineer with each variant. So they leave it alone. Here are initial iPhone pics of the active Turbo wings, set on top of the GT3 The wing development / mechanics are done. The only thing left is to make the web pages, shoot real pics, and go out for some track days. Questions are welcome.
#86
The sections of track you initially mention are the easy ones, max DF at Braking and least on the straight, but with the variety of tracks around I don't see how one set of algorithms could fit every track. That would be to say no tuning necessary ever, and that sounds far fetched for anything on a track car.
What are the algorithms based on? How do they adjust for grip in the tires? HP/Weight of the car? Do they have to be re-tuned with adjustments to the car? Does it measure slip angles?
I'm also confused at 50/50 front/rear DF because that seems very vague for the various different kinds of cars with different weight balances. And how many of the GT cars can actually match rear DF in the front? Seems like the rear in RWD race cars (which is what most are) will need more DF over the powered wheels anyways.
What are the algorithms based on? How do they adjust for grip in the tires? HP/Weight of the car? Do they have to be re-tuned with adjustments to the car? Does it measure slip angles?
I'm also confused at 50/50 front/rear DF because that seems very vague for the various different kinds of cars with different weight balances. And how many of the GT cars can actually match rear DF in the front? Seems like the rear in RWD race cars (which is what most are) will need more DF over the powered wheels anyways.
Yeah, you can use aero to chase suspension, tire, and other setup issues. But you shouldn't. It's not the fastest way around the track, and the "aero fix" will change exponentially as a function of speed, whereas most other traction / suspension parameters don't. So you might solve a handling issue at one speed, and then create issues somewhere else.
Of course, we could make the wings more advanced. Like I said, if you want to pay $500k, we will do that for you.
#88
This is really simple. The straightaway angle is minimum drag (plus / minus some level of stability). The Braking angle is the most efficient aero angle to stop your car. That is the same for 95% of situations. And, the angle of attack of the wing during cornering, should balance the front aero.
Yeah, you can use aero to chase suspension, tire, and other setup issues. But you shouldn't. It's not the fastest way around the track, and the "aero fix" will change exponentially as a function of speed, whereas most other traction / suspension parameters don't. So you might solve a handling issue at one speed, and then create issues somewhere else.
Of course, we could make the wings more advanced. Like I said, if you want to pay $500k, we will do that for you.
Yeah, you can use aero to chase suspension, tire, and other setup issues. But you shouldn't. It's not the fastest way around the track, and the "aero fix" will change exponentially as a function of speed, whereas most other traction / suspension parameters don't. So you might solve a handling issue at one speed, and then create issues somewhere else.
Of course, we could make the wings more advanced. Like I said, if you want to pay $500k, we will do that for you.
I'm not suggesting that the wheel be reinvented, just inquiring about the tuning of the wing, because someone will want to tune it for cornering balance at some point if they haven't already.
#90
This is a common misconception.
The front / rear aero balance does not change as a function of track. What changes is your tire pressure, tire temp, track temp, road surface, etc. Everything changes EXCEPT the aero. Chasing these changes with aero is not the right way to setup a car.
Your aero has a very week dependence on altitude, and a strong dependence on ride height / car pitch. So, if you don't adjust ride height, the aero is the same.
The front / rear aero balance does not change as a function of track. What changes is your tire pressure, tire temp, track temp, road surface, etc. Everything changes EXCEPT the aero. Chasing these changes with aero is not the right way to setup a car.
Your aero has a very week dependence on altitude, and a strong dependence on ride height / car pitch. So, if you don't adjust ride height, the aero is the same.
I guess that's what I'm trying to say, front aero can also change with various pieces, and hardly ANY of them are tested for efficiency, meaning the balancing the front aero is easier said than done. For most of us, that balance is found by trial and error doing laps. And the front/rear aero balance for one track will not be the same for every track, top level pro or not.
I'm not suggesting that the wheel be reinvented, just inquiring about the tuning of the wing, because someone will want to tune it for cornering balance at some point if they haven't already.
I'm not suggesting that the wheel be reinvented, just inquiring about the tuning of the wing, because someone will want to tune it for cornering balance at some point if they haven't already.