Aerodynamic Lift

[A2WindTunnel]

Racers often focus only on drag when thinking about aerodynamics, but there are 2 major factors to consider in racecar aerodynamics.

#1 Drag
#2 Lift (negative -Lift = Downforce)

More than just looking at total lift though is actually breaking it down into front and rear lift to determine the overall balance of the racecar.  In this picture of Gary & Pam Beneke's 1971 Daytona you can see 3 different 2010 Maxton meets and 3 different aerodynamic configurations of the racecar.  

Since this is a customer’s test I will not go into specifics or post data of what changes were made since they paid the money to develop it in the wind tunnel, but I will just point out some various things in the pictures.


In the top (April) picture the car was run for the first time before it went to a wind tunnel to establish a baseline and take notes of any handling issues.  Notice the how the front of the car is "lifting" upward by the fender gap.  This was at 181 mph and the racecar is 4000lbs.  The driver (Gary) said that the car was very unstable and steering all over the track and it was all he could do to keep it between the traps.  

In the middle (May) picture the car was run for the second time following a wind tunnel test/development session.  The initial baseline data did show a major lift problem on the nose of the car which was consistent with the first picture and negative lift on the rear (downforce) which yields a major aerodynamic imbalance.  After 2 hours in the tunnel the lift problem was corrected.  Since the wind tunnel test was 1 day before Maxton some of the modifications could not be completed because of the fabrication that would have to be done to get it in the optimum configuration.  Gary ran the car a second time and said it was a night and day difference in handling.  The car drove straight (190 mph) and drove much better than the first Maxton meet.  You can see in the second picture that the nose was still lifting a bit as confirmed by the wind tunnel results in this configuration where there was still a little bit of lift on the nose.

In the lower (June) picture the car was modified to the optimum configuration (negative lift front and rear) for the June meet where Gary ran 193 mph.  In his words “I drove the car with one hand” and his right hand went from the shifter to the parachute lever.    

[A2WindTunnel]

Photos courtesy of:

David Whealon

DW Photos: www.dwphotosonline.com
.

[Glen]

Great example, thanks for sharing. Like the saying the picture is worth a 1000 words.

[doug odom]

I remember Chrysler telling us 40 years ago that this car liked 1 1/2 degrees body rake and the spoiler at 60 degrees to the world.  Looks like that is about where you ended up. Air just never changes.. LOL

[Cajun Kid]

Dave,

Thanks for the info and the pictures.  I learned a lot helping in the tunnel in May.

My new 1953 Studebaker build is within 10 days of being complete.

That will not leave me any time to get it to the tunnel before I go to Maine (leaving on the 28th)

I had hoped to get a 2 hour baseline test in A2 before we go to Maine,, but looks like we have run out of time.

As soon as time permits I will get with you,,

Thanks again

Charles

[46champ]

When did double element rear wings show up on Daytonas?

[hotrod]

When did double element rear wings show up on Daytonas?

To my knowledge the OEM wing was always a single air foil design with limited pitch adjustment.

Larry

[blackslax]

When did double element rear wings show up on Daytonas?

I believe the double wing showed up on the Daytona about the time these guys wanted to go over 200 and could not keep it on the ground.

[A2WindTunnel]

When did double element rear wings show up on Daytonas?

Below in "blod font " is straight off the Gary & Pam's website: www.71wingcars.com

"CHRYSLER'S AERODYNAMIC WIND TUNNEL TEST REPORT:   Gary & Pam Beineke built their 1971(G-Series) wingcars based upon results from a secret wind tunnel test report Chrysler had conducted in early 1970 on the new 71 Dodge and Plymouth B-bodies.  No full scale cars were ever built...until now.

All of Pam & Gary's creations have been featured in Mopar Collector's Guide, Mopar Action, Mopar Enthusiast, Musclecar Enthusiast, Mopar Max, Hot Rod TV, and most notably, three of their 'Phantoms" have been featured in Hot Rod Magazine.

G-SERIES DESIGNS:  After  building the 71 Wingcars, Pam & Gary continued the theme of creating 'what if' cars with XCON, a one of a kind, 71 GTX convertible.   In 2008, Pam & Gary completed the SRT-71/SERPENT, another 'what if' concept of their vision of a new Charger.  In 2009, they finished their next project, JET X, a 1971-2  GTX  Plymouth Exterior Styling studio car, built using photos from 1968 & 9. JET X was debuted in the "T" bldg at Carlisle.  It was featured on the cover of Mopar Action and soon to be featured in Mopar Enthusiast."

 The duel element '71 wing car (G-series) was developed in a wind tunnel as a 3/8 scale model, but NASCAR made a rule against the wing cars before a full-scale version was ever built or raced.  Gary & Pam obtained wind tunnel data from the testing that was conducted, and built the car to the "new" modifications that would have been built had NASCAR allowed them to continue racing in the series.  An interesting note; Gary Romberg who was head of racecar aerodynamics for Chrysler (retired) was the aerodynamist on the wing cars back in the day, and now works at AeroDyn & A2.  So when the car came to test in the A2 tunnel he was able to see a full-scale version that had been built from his testing/notes over 40 years earlier.

They have some really unique “what if” cars they have built on their website www.71wingcars.com and I think they plan on racing at LAFB at the end of the month as well.
.

[bvillercr]

Nice looking car.  What class is that car legal in?

[dw230]

"The duel element '71 wing car (G-series) was developed in a wind tunnel as a 3/8 scale model, but NASCAR made a rule against the wing cars before a full-scale version was ever built or raced."

This is good to know.

DW
Chief Impound Steward

[4-barrel Mike]

ECTA: 7100 6/26/10 9:30 AA/GCT Gary Beineke   Gary Beineke 191.43147 205.01100 June 2010

Does the ECTA publish a list/breakout of their classes somewhere not in the rulebook

Mike

[1212FBGS]

so this Gary dude spent a lot of time developing a scale model and it was outlawed even before he got a chance to build and race it.... then 40 years later someone built his car tested it, and set a record with it..... how fricken cool is that?..... gotta love our sport
Kent

[Glen]

ECTA rule book pg 5o  5.D.7 circle track.
Wings and nurf bars that give aerodynamic aid are not permitted.  Interesting

[Stan Back]

Maybe more than interesting.