NEW CRAWFORD WING FOR GT3
12-17-2014, 02:09 PM
#46
Burning Brakes
Thread Starter
Lane.... Thanks for the valuable information. Really much appreciated. I actually thought about eliminating that third brake light and plugging the hole with a specially formed piece that can restore the trailing edge of the wing and hopefully pick up some additional down force from the stock wing. By any chance did they share with you the actual downforce figures for the stock GT3 wing (both positions) or the new wing they designed for you? Also curious if you ever tried the stock wing adjusted to the second position where it supposed to give you higher down force? Just curious if that helped with tail wag at 150 mph braking.
Again great post,.... Thank you , and look forward to hear more from you about future modifications or adjustments to your car. Mark
Again great post,.... Thank you , and look forward to hear more from you about future modifications or adjustments to your car. Mark
The angular adjustment on the original GT3 Wing is very small for a Race Wing.
I just set mine to maximum Angle and my comments on the differences with the Crawford Wing were at a single setting. I understand Sport Auto measured it at 65 Lbs @ 130 MPH, about half of what they measured on the 991 Turbo's downforce. Both are mounted very low. Generally Race Car Wings have downforce numbers 10 X higher depending on their Chord, mounting position, Angle of Attack adjustment, Gurney Flap dimensions etc. Of course Downforce changes dramatically with speed. 1/2 the speed reduces downforce to 1/4. Pushed, all Wing Manufacturers admit their numbers should be considered approximations rather than firm numbers.
Turns out Downforce numbers are VERY difficult to generate accurately. Measuring
Aero modifications just have too many variables. Even with the huge expense of renting Wind Tunnels, the actual numbers are still elusive with "Rolling Road" Wind Tunnels generating numbers differing even more than the differing Wind Tunnel Air Volumes are.
F1 uses transducers strategically located to measure suspension stresses,
prohibitively expensive without Mega Budgets. Other race teams use Video to
measure suspension deflection but even that is suspect with differing loads
being transferred to different sections of the car depending on outside air temps track temps, changing air densities, transient wind velocity vectors. and whether the car is accelerating or braking which it is doing constantly around a race course. Combine that with the differing reactions and balance of front and rear aero to wind velocity and you can see the complexity of coming up with accurate or stable numbers.
Crawford does use several nearby Wind Tunnels for early development, but the final sign-off on new race car designs or components such as Wings, Splitters, Diffusers, Etc is done the old fashioned way with lap times and feedback from a Professional and Consistent Race Car Driver. Crawford uses a nearby race track for measuring Lap times and driver feedback on handling. Nice to know we humans are still needed LOL.
12-17-2014, 02:27 PM
#47
Three Wheelin'
Hi Mark,
The angular adjustment on the original GT3 Wing is very small for a Race Wing.
I just set mine to maximum Angle and my comments on the differences with the Crawford Wing were at a single setting. I understand Sport Auto measured it at 65 Lbs @ 130 MPH, about half of what they measured on the 991 Turbo's downforce. Both are mounted very low. Generally Race Car Wings have downforce numbers 10 X higher depending on their Chord, mounting position, Angle of Attack adjustment, Gurney Flap dimensions etc. Of course Downforce changes dramatically with speed. 1/2 the speed reduces downforce to 1/4. Pushed, all Wing Manufacturers admit their numbers should be considered approximations rather than firm numbers.
Turns out Downforce numbers are VERY difficult to generate accurately. Measuring
Aero modifications just have too many variables. Even with the huge expense of renting Wind Tunnels, the actual numbers are still elusive with "Rolling Road" Wind Tunnels generating numbers differing even more than the differing Wind Tunnel Air Volumes are.
F1 uses transducers strategically located to measure suspension stresses,
prohibitively expensive without Mega Budgets. Other race teams use Video to
measure suspension deflection but even that is suspect with differing loads
being transferred to different sections of the car depending on outside air temps track temps, changing air densities, transient wind velocity vectors. and whether the car is accelerating or braking which it is doing constantly around a race course. Combine that with the differing reactions and balance of front and rear aero to wind velocity and you can see the complexity of coming up with accurate or stable numbers.
Crawford does use several nearby Wind Tunnels for early development, but the final sign-off on new race car designs or components such as Wings, Splitters, Diffusers, Etc is done the old fashioned way with lap times and feedback from a Professional and Consistent Race Car Driver. Crawford uses a nearby race track for measuring Lap times and driver feedback on handling. Nice to know we humans are still needed LOL.
The angular adjustment on the original GT3 Wing is very small for a Race Wing.
I just set mine to maximum Angle and my comments on the differences with the Crawford Wing were at a single setting. I understand Sport Auto measured it at 65 Lbs @ 130 MPH, about half of what they measured on the 991 Turbo's downforce. Both are mounted very low. Generally Race Car Wings have downforce numbers 10 X higher depending on their Chord, mounting position, Angle of Attack adjustment, Gurney Flap dimensions etc. Of course Downforce changes dramatically with speed. 1/2 the speed reduces downforce to 1/4. Pushed, all Wing Manufacturers admit their numbers should be considered approximations rather than firm numbers.
Turns out Downforce numbers are VERY difficult to generate accurately. Measuring
Aero modifications just have too many variables. Even with the huge expense of renting Wind Tunnels, the actual numbers are still elusive with "Rolling Road" Wind Tunnels generating numbers differing even more than the differing Wind Tunnel Air Volumes are.
F1 uses transducers strategically located to measure suspension stresses,
prohibitively expensive without Mega Budgets. Other race teams use Video to
measure suspension deflection but even that is suspect with differing loads
being transferred to different sections of the car depending on outside air temps track temps, changing air densities, transient wind velocity vectors. and whether the car is accelerating or braking which it is doing constantly around a race course. Combine that with the differing reactions and balance of front and rear aero to wind velocity and you can see the complexity of coming up with accurate or stable numbers.
Crawford does use several nearby Wind Tunnels for early development, but the final sign-off on new race car designs or components such as Wings, Splitters, Diffusers, Etc is done the old fashioned way with lap times and feedback from a Professional and Consistent Race Car Driver. Crawford uses a nearby race track for measuring Lap times and driver feedback on handling. Nice to know we humans are still needed LOL.
GOOD STUFF FASTLANE!!!! How was the install? What does the finish look like at the junction? Is it still an unfinished look? Could it be a 20 minute install for a track weekend thing??
12-17-2014, 11:24 PM
#50
Burning Brakes
Thread Starter
One of the 2 mounting Pillars with Brakelight
Front of Wing with its 2 Mounting Pillars secured by original 2 Bolts on each Pillar. After removing,<br/>place original wing into slots, tighten screws and insert original plug into original harness <br/>connector. No soldering or rewiring required
Rear of Wing with Brakelights
12-17-2014, 11:54 PM
#51
Burning Brakes
Thread Starter
on its very first track event at Daytona, I'm convinced more rear downforce is a VERY good thing for any GT3 that is tracked.
Not certain about attending 48 Hrs Sebring Event. I'm instructing for many different Clubs now and watching my Buddies having all that fun without me in their race is painful.
12-17-2014, 11:59 PM
#52
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
I remember when Porsches were meant to be driven to the tracked, raced, and then driven home. That philosophy went back to before James Dean lost his life doing exactly that. That seems to be dying out.
12-18-2014, 12:05 AM
#53
Race Director
FastlaneTurbo will you be at the Chin Homestead event Jan 4-5th?
I think the wing looks as good are the 997 GT3RS wings looked and I loved those.
Also it seems the 991 GT3 guys are more conservative than the 997 GT3RS guys I used to track with and that were all over the 997GT3 forum. I think most would like this 991GT3 wing better if the gold leaf and red strip stickers were not on the car and wing uprights as the look would flow a lot more.
Ok...that my .02....see ya!
I think the wing looks as good are the 997 GT3RS wings looked and I loved those.
Also it seems the 991 GT3 guys are more conservative than the 997 GT3RS guys I used to track with and that were all over the 997GT3 forum. I think most would like this 991GT3 wing better if the gold leaf and red strip stickers were not on the car and wing uprights as the look would flow a lot more.
Ok...that my .02....see ya!
12-18-2014, 12:07 AM
#54
Three Wheelin'
[QUOTE=FastLaneTurbo;11884843]The switch from the original Wing to the new one can easily be done in 20 Minutes or less. Just remove the four bolts holding the Wing, unplug the brake light harness plug and lift the new Wing clear. Insert the original Wing into the four empty slots, Reinsert those 4 bolts, Tighten, and reconnect the original harness plug. Piece of cake!
Thanks.... very simple and do able for a weekend change into Superman wing, then back to Clark Kent when done.
Thanks.... very simple and do able for a weekend change into Superman wing, then back to Clark Kent when done.
12-18-2014, 12:40 AM
#55
Rennlist Member
Hi Mark,
The angular adjustment on the original GT3 Wing is very small for a Race Wing.
I just set mine to maximum Angle and my comments on the differences with the Crawford Wing were at a single setting. I understand Sport Auto measured it at 65 Lbs @ 130 MPH, about half of what they measured on the 991 Turbo's downforce. Both are mounted very low. Generally Race Car Wings have downforce numbers 10 X higher depending on their Chord, mounting position, Angle of Attack adjustment, Gurney Flap dimensions etc. Of course Downforce changes dramatically with speed. 1/2 the speed reduces downforce to 1/4. Pushed, all Wing Manufacturers admit their numbers should be considered approximations rather than firm numbers.
Turns out Downforce numbers are VERY difficult to generate accurately. Measuring
Aero modifications just have too many variables. Even with the huge expense of renting Wind Tunnels, the actual numbers are still elusive with "Rolling Road" Wind Tunnels generating numbers differing even more than the differing Wind Tunnel Air Volumes are.
F1 uses transducers strategically located to measure suspension stresses,
prohibitively expensive without Mega Budgets. Other race teams use Video to
measure suspension deflection but even that is suspect with differing loads
being transferred to different sections of the car depending on outside air temps track temps, changing air densities, transient wind velocity vectors. and whether the car is accelerating or braking which it is doing constantly around a race course. Combine that with the differing reactions and balance of front and rear aero to wind velocity and you can see the complexity of coming up with accurate or stable numbers.
Crawford does use several nearby Wind Tunnels for early development, but the final sign-off on new race car designs or components such as Wings, Splitters, Diffusers, Etc is done the old fashioned way with lap times and feedback from a Professional and Consistent Race Car Driver. Crawford uses a nearby race track for measuring Lap times and driver feedback on handling. Nice to know we humans are still needed LOL.
The angular adjustment on the original GT3 Wing is very small for a Race Wing.
I just set mine to maximum Angle and my comments on the differences with the Crawford Wing were at a single setting. I understand Sport Auto measured it at 65 Lbs @ 130 MPH, about half of what they measured on the 991 Turbo's downforce. Both are mounted very low. Generally Race Car Wings have downforce numbers 10 X higher depending on their Chord, mounting position, Angle of Attack adjustment, Gurney Flap dimensions etc. Of course Downforce changes dramatically with speed. 1/2 the speed reduces downforce to 1/4. Pushed, all Wing Manufacturers admit their numbers should be considered approximations rather than firm numbers.
Turns out Downforce numbers are VERY difficult to generate accurately. Measuring
Aero modifications just have too many variables. Even with the huge expense of renting Wind Tunnels, the actual numbers are still elusive with "Rolling Road" Wind Tunnels generating numbers differing even more than the differing Wind Tunnel Air Volumes are.
F1 uses transducers strategically located to measure suspension stresses,
prohibitively expensive without Mega Budgets. Other race teams use Video to
measure suspension deflection but even that is suspect with differing loads
being transferred to different sections of the car depending on outside air temps track temps, changing air densities, transient wind velocity vectors. and whether the car is accelerating or braking which it is doing constantly around a race course. Combine that with the differing reactions and balance of front and rear aero to wind velocity and you can see the complexity of coming up with accurate or stable numbers.
Crawford does use several nearby Wind Tunnels for early development, but the final sign-off on new race car designs or components such as Wings, Splitters, Diffusers, Etc is done the old fashioned way with lap times and feedback from a Professional and Consistent Race Car Driver. Crawford uses a nearby race track for measuring Lap times and driver feedback on handling. Nice to know we humans are still needed LOL.
I am well aware of how approximate the manufacturers numbers and that they are preliminary at best. My background is hydraulic design so I am always interested and fascinated by a good airfoil wing design.
The reason for asking for the numbers was just to establish a baseline. I have currently couple of young engineering interns working for my company and wanted to give them some ideas for their engineering design project for their senior year, and I was thinking about having them model the currentl GT3 wing and run some FEA modeling and perhaps they can come up with a new modified wing. So it is nice to able to give them some downforce data to establish a baseline, even though these numbers are just an approximation. Not sure if they will be interested at the end to pick such a project, but it is worth a shot. If they end up picking such a project I will share with all their findings and their proposed new wing.
But I am really impressed and interested in the Crawford wing and especially how easy to swap before a track event. They are very reputable and I am really impressed that someone like Crawford would take the time to accommodate you and able to come up with a new design for you in few days. These guys certainly deserve our appreciation and support. Could I trouble you to PM me the cost.
Finally what happened to your friend who had the accident with the 991 GT3. Is this recent and was there any posts or news about this unfortunate accident. It is just the first time I heard about it.
Again thanks for all of your help and also the valuable information. Mark
12-18-2014, 11:47 AM
#58
Burning Brakes
Thread Starter
Good stuff lane and very informative. Really appreciate you taking the time to educate us.
I am well aware of how approximate the manufacturers numbers and that they are preliminary at best. My background is hydraulic design so I am always interested and fascinated by a good airfoil wing design.
The reason for asking for the numbers was just to establish a baseline. I have currently couple of young engineering interns working for my company and wanted to give them some ideas for their engineering design project for their senior year, and I was thinking about having them model the currentl GT3 wing and run some FEA modeling and perhaps they can come up with a new modified wing. So it is nice to able to give them some downforce data to establish a baseline, even though these numbers are just an approximation. Not sure if they will be interested at the end to pick such a project, but it is worth a shot. If they end up picking such a project I will share with all their findings and their proposed new wing.
But I am really impressed and interested in the Crawford wing and especially how easy to swap before a track event. They are very reputable and I am really impressed that someone like Crawford would take the time to accommodate you and able to come up with a new design for you in few days. These guys certainly deserve our appreciation and support. Could I trouble you to PM me the cost.
Finally what happened to your friend who had the accident with the 991 GT3. Is this recent and was there any posts or news about this unfortunate accident. It is just the first time I heard about it.
Again thanks for all of your help and also the valuable information. Mark
I am well aware of how approximate the manufacturers numbers and that they are preliminary at best. My background is hydraulic design so I am always interested and fascinated by a good airfoil wing design.
The reason for asking for the numbers was just to establish a baseline. I have currently couple of young engineering interns working for my company and wanted to give them some ideas for their engineering design project for their senior year, and I was thinking about having them model the currentl GT3 wing and run some FEA modeling and perhaps they can come up with a new modified wing. So it is nice to able to give them some downforce data to establish a baseline, even though these numbers are just an approximation. Not sure if they will be interested at the end to pick such a project, but it is worth a shot. If they end up picking such a project I will share with all their findings and their proposed new wing.
But I am really impressed and interested in the Crawford wing and especially how easy to swap before a track event. They are very reputable and I am really impressed that someone like Crawford would take the time to accommodate you and able to come up with a new design for you in few days. These guys certainly deserve our appreciation and support. Could I trouble you to PM me the cost.
Finally what happened to your friend who had the accident with the 991 GT3. Is this recent and was there any posts or news about this unfortunate accident. It is just the first time I heard about it.
Again thanks for all of your help and also the valuable information. Mark
Re giving your engineering students some insight into the development of R&D
projects such as this wing, I am attaching the original Engineering work on this wing which Crawford supplied to me showing the internal details. The metal mounting brackets shown required additional composite cladding to match the curves of the original GT3's pillars. Turned out to be a much larger project than I imagined going into it - which I'm certain you will not be surprised to hear, as
most Engineering projects, when 90% completed, are only half done. LOL!
Wing with Endplates
Endplates and embedded Mounting Tabs
Oval Slotted Mounting Tabs for Wing Angle Adjustment
Endplates/ Tabs / Wing Interface
Wing Assembly Complete
Tab / Wing / Endplate
12-18-2014, 12:14 PM
#59
Burning Brakes
Thread Starter
FastlaneTurbo will you be at the Chin Homestead event Jan 4-5th?
I think the wing looks as good are the 997 GT3RS wings looked and I loved those.
Also it seems the 991 GT3 guys are more conservative than the 997 GT3RS guys I used to track with and that were all over the 997GT3 forum. I think most would like this 991GT3 wing better if the gold leaf and red strip stickers were not on the car and wing uprights as the look would flow a lot more.
Ok...that my .02....see ya!
I think the wing looks as good are the 997 GT3RS wings looked and I loved those.
Also it seems the 991 GT3 guys are more conservative than the 997 GT3RS guys I used to track with and that were all over the 997GT3 forum. I think most would like this 991GT3 wing better if the gold leaf and red strip stickers were not on the car and wing uprights as the look would flow a lot more.
Ok...that my .02....see ya!
