ChampCar Tech Desk

The tech desk is used to ask technical questions and is not to be used as a post race tech line or to phish for how others built their cars.
Please reference the BCCR as most questions submitted to the TechDesk can be answered by reading the BCCR.
You can download the BCCR here:

2020-01-10 - Rear wing width

Q 1.
As I am about to order a new rear wing I wanted to confirm how wide I am able to go. Rules state no wider than the car not including side mirrors, my car is flared with steel flares welded in front and bolted on in back, but I heard a comment that a team needed to cut down the width of their wing to match the stock width of the car. I just wanted some clarification on this as my flares to add about 2 inches to each side of the car.

Q 2.
Per BCCR 4.3.2 " Aerodynamic devices not to exceed width of bodywork (fenders, bumpers, doors) when viewed from above. Note: Side mirrors are not included in bodywork width"
Per BCCR requiring fenders cover the tires, many teams have "rolled" their fenders to increase the width of the fenders. In our case, that width has been increased up to 8 inches in total. 
Fenders, when viewed from above, can greatly exceed the OEM width of the vehicle and that per the BCCR this would allow aero elements to also exceed the OEM width, so long as the width is less than the modified width 4.3.2.


The maximum width of a wing or splitter is determined by the OE body shape and not by any bodywork added to the car that makes it appear wider. In your case, you cannot include the new fender flares in your measurement and instead must measure from the OE steel fender dimensions.

Michael Chisek

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