Swan neck wing for Seven

[searya]

Lost control 2 times last year on track so decided to make my winter project adding some rear aero/downforce. Attached are some pics of the plastic prototypes and the final product. 

 

My son and I used onShape a free online CAD program to design the mounts then did like 10 different iterations of 3d plastic models before having Send Cut Send cut the final version out of aluminum. 

 

We also designed in a slot for a big servo motor. The plan there is to later add a second element with drs capability.

 

For the drs capability I bought an arduino microprocessor with an accelerometer and gyroscope. I then coded it so that if I hit the brakes, have x amount of g force or yaw rate the second element will close. Else it will open after a second (that is while on a straight). 

 

I attached the mounts to the angled part of the roll bars.  My thought there was I can raise it higher/more forward or lower and backwards plus change the angle of attack in the wing. Also the wing can be removed entirel with 4 bolts. 

 

In all positions the wing will be at best right over the rear suspension (high/more forward) or behind the rear trunk (low/back).  So once I get it track tested I will see if any front aero is needed as well. 
 

 

[Croc]

49 minutes ago, searya said:

Lost control 2 times last year on track ....

 

Clearly you have never seen a USA7s HPDE at NJMP?  Only two times....

 

I laughed at the Nine Lives Racing!

 

Lovely work to fabricate the wing though!  Is it allowed to be wider than the rear track?  Maybe thats just a race rule I remember?  How much did you go up in spring weight to make the aero work?

[Croc]

57 minutes ago, searya said:

 

 

 

 

Excellent, you both enjoy good quality wine while fabricating - well done!  Good to see I am not the only civilized person at USA7s! 

 

@JohnCh I want a wine cheers emoticon/smiley thingy!

 

[JohnCh]

13 minutes ago, Croc said:

@JohnCh I want a wine cheers emoticon/smiley thingy!

 

Sorry, this is more of an accessible beer site than a snobby wine site. 

[IamScotticus]

Thanks for onShape and send cut send.

 

DRS is?

[11Budlite]

14 minutes ago, IamScotticus said:

DRS is?

 

Drag Reduction System. As used on F1 cars.

[searya]

17 hours ago, Croc said:

 

Clearly you have never seen a USA7s HPDE at NJMP?  Only two times....

 

I laughed at the Nine Lives Racing!

 

Lovely work to fabricate the wing though!  Is it allowed to be wider than the rear track?  Maybe thats just a race rule I remember?  How much did you go up in spring weight to make the aero work?

Total Weight of wing and uprights was 21lbs.  Originally I wanted to build the wing from carbon fiber with a foam core.  But i really do hate making carbon fiber and so far i have been too cheap to buy one.  I still may do it though sometime when i am bored :).

 

As to with the wing is 71" wide and goes right to the edge of the tires.  I just HPDE days so no rules for me to follow

[searya]

17 hours ago, JohnCh said:

 

Sorry, this is more of an accessible beer site than a snobby wine site. 

Don't worry we only buy box wine

[JohnCh]

2 minutes ago, searya said:

Don't worry we only buy box wine

 

I can tell you're not a wine snob. They wouldn't let glasses of red and white get that close together. It would feel too much like a virtual Rose. Now Croc on the other hand...

[searya]

15 hours ago, IamScotticus said:

Thanks for onShape and send cut send.

 

DRS is?

you bet.

 

onShape is fantastic.  Work online, no big computer needed to run the software, easy to collab and do stuff with a kid at college etc.

 

And after i had the final all it took was upload to send cut send and the final was exactly like the 3d models.

 

If anyone is thinking of doing the same mount location, all that would be needed is to change the CAD model to match the angel of your rollbar (mine was 55 degree angle)

[Reiver]

Nice fabrication work there.... 

[IamScotticus]

5 hours ago, searya said:

Total Weight of wing and uprights was 21lbs.

More sprung weight in the back is good. Watch the wear on those A arm bushes 

[Origin7]

Excellent use of the 3D printer! The ability to quickly and inexpensively iterate and try new things is so valuable.

[searya]

On 1/11/2026 at 3:31 PM, IamScotticus said:

More sprung weight in the back is good. Watch the wear on those A arm bushes 

Will do and guess I am also due for a new corner balancing now too.

[searya]

On 1/12/2026 at 7:58 AM, Origin7 said:

Excellent use of the 3D printer! The ability to quickly and inexpensively iterate and try new things is so valuable.

Thanks.  Next up is to play with some front wing designs in case i need to balance out my new rear wing.

[Origin7]

2 hours ago, searya said:

Thanks.  Next up is to play with some front wing designs in case i need to balance out my new rear wing.

I can imagine a diffuser on the back as well. 

 

It looks like you can get a load cell and amplifier to work with Arduino. Integrating the load cells would be a little tricky, but it would be fun to collect some data and experiment with different attack angles.   

[searya]

46 minutes ago, Origin7 said:

I can imagine a diffuser on the back as well. 

 

It looks like you can get a load cell and amplifier to work with Arduino. Integrating the load cells would be a little tricky, but it would be fun to collect some data and experiment with different attack angles.   

Funny you say that.  A few years ago i created a thread on how to create a Carbon Fiber Rear diffuser.  Didn't do a great job of showing the final product in the thread though and the diffuser was off in the pics above but will be back on for the new season!

 

For the load cell and arduino option what was your thought for placement to get measurements?  I would love to see what kind of downforce different heights and angles provided.

 

[Croc]

4 hours ago, searya said:

Thanks.  Next up is to play with some front wing designs in case i need to balance out my new rear wing.

I mean it’s not as if a car with a reputation for high speed understeer from a light front end, heavily encouraged from lots of rear downforce, will need a front wing…. 😛

 

i am glad you have good fabrication skills!  
 

Looking forward to instalment number 2!