Swift Engineering Wind Tunnel Tour for GT Owners

[analogdesigner]

Swift Engineering Wind Tunnel Tour for GT Owners

As some of you may know-- during the Ford GT development, a 45% scale factor model of the GT body with chassis was constructed for evaluation and optimization at the Swift Engineering High-Tech Wind Tunnel in San Clemente, CA.
http://www.swiftengineering.com/06Other/Windtunnel/Windtunnel.htm

I would like to arrange a ‘Technical GT Symposium’ that would involve a short lecture by one of the Swift Engineering experts involved in the evaluation as well as a tour of the facility. A ‘question and answer’ session would also be included.

Swift Engineering was one of the vendors responsible for performing critical aerodynamic testing that allows our GT to exceed 200 MPH while maintaining downforce necessary for proper handling. Since San Clemente is my hometown and Swift Engineering is just a few minutes away from my home, I thought that it would be very interesting to host this type of tour- one that would be fun, informative, and memorable.

I have a few questions to ask of you to determine the feasibility of making this event successful:

1. How many of you GT owners out there would be interested in participating? Yes or No

2. Would you prefer a Saturday event opposed to a weekday event? Saturday yes--- Weekday________________.

3. Since this is going to be a very technical seminar/tour, please consider only inviting 1 additional person in your party.

4. I would like to follow the tour with a brunch/lunch at a local restaurant. Would you be interested in attending? Yes or No

If yes , how many in your party _______ and do you have any particular preferences as to venue? ____________________________________.

Please respond back to gtsaver@cox.net by Friday, April 28, 2006.


Regards,

Jay Philippbar (949) 366-1211

 

[Black2003Cobra]

If you get a chance, ask them if they know what the drag coefficient is. The original GT40 had Cd = 0.43, from what I've read. Reportedly, they were targeting < 0.4 on the new GT. Oh, and see if they can tell you the frontal area, too. Thanks!

 

[Craig]

Great Idea, count me in. I would prefer a Saturday. Do you know how many cars/people that Swift can handle? If there is extra room I am certian several members from the San Diego Shelby club would like to attend as well.

Craig

 

[todd]

I would go.

 

[AMB]

I will go too !!!

 

[californiacuda]

Me too

 

[BlackICE]

I would love to go, but I will have to check on the dates when set. If I cannot make it. I would like to know the follow:

1. Cd
2. Frontal area
3. Downforce/lift measured at front and rear tires at various speeds.
4. Air flow into and out of the various vents. e.g. In the engine compartment we have the rear vents on the back side, louvers and vents on the engine cover, what is the direction and flow rates of the air into or out of those vents. I am assuming that the vents on the B pillars are for the engine's air intake.

BlackICE

 

[californiacuda]

I have carefully measured my GT and come up with 19.95 sq ft of frontal area. Using this number and the air resistance number of 874 lbs at 200mphf rom a magazine article previously mentioned in this forum and estimating the rolling resistance at around 100lbs, I came up with a drag coefficient of .388.

I have recently purchased a device from a company called Baun that measures deceleration and time very precisely and I will know the exact rolling resistance and drag coefficient numbers.

I called Swift and they would give me no info for the GT, they said that all of the data was Ford's property and they could not divulge anything.

 

[analogdesigner]

Data for GT

I have carefully measured my GT and come up with 19.95 sq ft of frontal area. Using this number and the air resistance number of 874 lbs at 200mphf rom a magazine article previously mentioned in this forum and estimating the rolling resistance at around 100lbs, I came up with a drag coefficient of .388.

I have recently purchased a device from a company called Baun that measures deceleration and time very precisely and I will know the exact rolling resistance and drag coefficient numbers.

I called Swift and they would give me no info for the GT, they said that all of the data was Ford's property and they could not divulge anything.

C-cuda,

I am sure that Swift wouldn't give you any of their customer's data! You are certainly more "hard-core" than I am when it comes to drag coefficient. I really like "hard" numbers and perhaps a call to the right person at Ford may accomplish this!

BlackICE, right now the date is floating since there are many things that can influence it.

I will keep everyone posted on this event!

Thanks,

Jay
www.gtsaver.com

 

[californiacuda]

Does anybody know who to contact a Ford for aerodynamic info?

 

[satx]

I have carefully measured my GT and come up with 19.95 sq ft of frontal area. Using this number and the air resistance number of 874 lbs at 200mphf rom a magazine article previously mentioned in this forum and estimating the rolling resistance at around 100lbs, I came up with a drag coefficient of .388.

I think you are very close with the Cd. The most Ford has said was "under .39". I believe the frontal is ~19.2 - 19.5 sq ft.

 

[analogdesigner]

Contact info at Ford

Does anybody know who to contact a Ford for aerodynamic info?

C-cuda,

The original persons at Ford authored an SAE article in 2004 titled "2005 Ford GT-Vehicle Aerodynamics-Updating a Legend." This can be found starting on page 43 of the SAE International book "The Ford GT." The guys at Ford to contact should be:

1. Kent E. Harrison, (313) 206-8385, kharriso@ford.com

2. Michael P. Landry, (313) 594-0564, mlandry@ford.com

3. Thomas G. Reichenbach, (313) 323-5503, treichen@ford.com

Hope this helps! Jay www.gtsaver.com

 

[californiacuda]

Thanks for the tip, I just emailed all 3

 

[analogdesigner]

Thanks for the tip, I just emailed all 3

Please let us know what they say! Thanks, Jay

 

[nthfinity]

what kind of aerodynamics/ fluid flow questions do you have?

i might be able to sneak a few answers by...

BTW, there is ever so little lift at the rear; all the actual d/f is applied at the nose of the car... that is why the small lip over the tail exists (besides the underbody work)

the little divets under the car are to cause more turbulant flow at the cross section; thus accellerating the air moving under the car; and furthermore; keeping it earthbound....

 

[analogdesigner]

Negative pressure region???

what kind of aerodynamics/ fluid flow questions do you have?

i might be able to sneak a few answers by...

BTW, there is ever so little lift at the rear; all the actual d/f is applied at the nose of the car... that is why the small lip over the tail exists (besides the underbody work)

the little divets under the car are to cause more turbulant flow at the cross section; thus accellerating the air moving under the car; and furthermore; keeping it earthbound....

I drove mine in a light rain the other day at high speeds and it is extremely stable. It doesn't "dance around" as easily as other cars would. I do not recommend that anyone drive fast under these conditions, I did this for a brief moment trying to get a feel for the car.

Do you know of a region at the rear of car, around the location of the exhaust pipes or the license plate, where the maximum negative pressure (suction) is?

Many thanks,
Jay

 

[californiacuda]

I believe that the cd is very high for the GT. The nose angles back toward the car at the hood line just in front of the headlights. If the lower front of the car was vertical (not angled back) and the front tires were not exposed to oncoming air, would the cd be improved. Also, would vortex generators help?

 

[sandiegored]

I would be interested as well. Jay, let me know the date you are looking at.

 

[nthfinity]

just to keep things straight; i've had a few years of aerospace engineering classes behind me; and am familiar with a fair amount... but my direct answers would come from other persons inside the blue oval... so bear in mind i dont know if they will give me an answer, or even if they know.

Jay, i have an odd question for you...
after driving in the rain, did you notice any collection in the undercarriage?
based on your question; you are thinking of doing something where the exhaust flows out more freely? tuning the length of your pipes would have a greater effect on exhaust velocities; i would think... as i'm sure you know, each cylinder fire is a compression, or high pressure zone, followed by a rarefaction... this, along with exhaust diameter makes the specific engine note. if the lenght its tuned just right, at the mouth of each exhaust header will be the lowest of pressures available to help draw the exhaust out more easilly.


californiacuda... the GT does have vortex generators; other people call them venturi tunnels. the major limiting factor is the venturi tunnels arent as extreme an angle as other uber cars like the Enzo, and the CGT; and the net force perpindicular to the motion of the air isn't as strong.

there are some general aids to high speed d/f of this, and other cars (with ground effect)... more stiffly sprung cars do better, as the air under the car remains predictable with a flatly cornering car.

ovbiously, lower to the ground; as reducing the volume of air also increces the velocity of the air... and with closed wheel cars, velocity actually causes more air to stream in from the side-sills; and further increases d/f potential.

anyway; i'll see if i can get in touch with one of my contacts; and see if a little research doesn't dig up an answer for you

 

[analogdesigner]

Negative pressure question

just to keep things straight; i've had a few years of aerospace engineering classes behind me; and am familiar with a fair amount... but my direct answers would come from other persons inside the blue oval... so bear in mind i dont know if they will give me an answer, or even if they know.

Jay, i have an odd question for you...
after driving in the rain, did you notice any collection in the undercarriage?
based on your question; you are thinking of doing something where the exhaust flows out more freely? tuning the length of your pipes would have a greater effect on exhaust velocities; i would think... as i'm sure you know, each cylinder fire is a compression, or high pressure zone, followed by a rarefaction... this, along with exhaust diameter makes the specific engine note. if the lenght its tuned just right, at the mouth of each exhaust header will be the lowest of pressures available to help draw the exhaust out more easilly.

anyway; i'll see if i can get in touch with one of my contacts; and see if a little research doesn't dig up an answer for you

nthfinity,

I cannot give you an accurate answer on the undercarriage as I did not pay enough attention when I washed my entire car today.

I will send you a PM! Thanks, Jay