Bourdais Tests LED Wheel Display

Sebastien Bourdais with experimental LED Tire Lights on course during practice for the GoPro Grand Prix of Sonoma at Sonoma Raceway — Photo Credit: John Cote

IndyCar and Sebastien Bourdais tested out an LED wheel display system during Friday practice before the season finale in Sonoma. The No. 11 machine ran with lights on both the front and rear wheels.

According to IndyCar’s press release, the LED’s “have the potential of displaying logos or words for commercial partners, race or car information or other programmed details.” The system is under consideration by IndyCar for inclusion on the 2016 cars.

If approved, these lights could show race information similar to the LED panels that were introduced onto the cars earlier this year – the current panels just show race position and pit stop times. Some ideas are different colors for the current flag conditions (yellow while under yellow, green while the race is green, etc.), black or red colors depending on the current tire that’s on, or different colors for current championship position (driver in first has red tires, second has blue, etc.).


There are a ton of different options for what can be done with these lights if they come to fruition for next season. Like the current LED panels, I was skeptical of the visibility of the lights at first, but that’s why IndyCar tested them at Sonoma during the day. Speed of Light Media owner Guy Margetson said “we’re testing three colors in the brightest light of the afternoon sunshine to see how it is displayed.” From the initial images, it looks pretty good.


What do you think of these tire panels? What kind of information would you like to see displayed during a race? Let me know in the comments below.


Check out some more images of the experimental LED lights below.


Photo Credit: John Cote

Sebastien Bourdais apexes Turn 9A during practice for the GoPro Grand Prix of Sonoma at Sonoma Raceway — Photo Credit: John Cote

Sonoma Raceway Engineering Guide

Scott Dixon rolls through the Turn 9 Chicane during the GoPro Grand Prix of Sonoma at Sonoma Raceway — Photo Credit: John Cote

IndyCar heads to Sonoma for the season finale this weekend with six drivers still eligible for the championship. Let’s take a look at the Engineering Guide for Sonoma Raceway in California.

Surface: Road Course
Distance: 2.385 miles
Laps: 85

Sonoma is IndyCar’s tenth road/street course of the season, and also one of the toughest. The track features very short straights (one is made out of the drag strip located at the circuit), an esses section, and a brake heavy hairpin that leads on to a curvy front stretch. Besides navigating a rolling start with other cars around them on a narrow front straight, drivers also need to be ready for the heavy braking section heading into turn 2. The steep turn coupled with the braking can upset the balance of the car and send drivers running wide in qualifying and at the start of the race. 


The things teams will need to focus on this weekend are downforce through the high speed corners and acceleration rather than top speed. Cars don’t really get a good chance to top out going around this track, but getting up to speed on the slightly longer straights is imperative. Through the esses, maintaining momentum can really help you close up on a car that is struggling through the section. The hairpin like corners of 4 and 6 will provide some good overtaking opportunities in addition to the “classic” hairpin that is turn 11. A poor run out of the final turn will make you a sitting duck to cars behind on the front straight.



Sonoma is unlike almost any of the other road courses this series competes on. It doesn’t have a trademark long straight like we see in Long Beach or St. Petersburg. Therefore, it’s going to require a setup unlike any of the other tracks. Chevy have won six of the nine road/street course races this year, and they seem to have the upper hand heading into Sonoma as well. Their aero kit has been the winner most of the season despite Honda’s recent push in winning two of the last five road course races. 

However, some of the reasons for Honda’s slower pace could be because of higher downforce levels on the stock aero kit setup. Their front wing element has always had downforce in mind, with three flap elements and two endplates holding two more flaps. This has slowed them down on the straights but will benefit them in the turns. Also, if you look at their rear pod (pictured in red below), you can see the curved bottom edge that serves as a diffuser for the car. It sucks the air out from beneath the car, lowering the air pressure and therefore increasing downforce without adding any additional drag. 



Chevy opted for an angle parallel (no curve up) to the ground which makes their diffuser less effective. I don’t know if it will allow them to outrace the Chevy’s and win, but it could certainly help make them more competitive on a track where mid to high speed corners are plenty.


Update: 8/29 – If you have any more questions about the cars or Sonoma Raceway (or IndyCar engineering in general), let me know in the comments below and I’ll do my best to answer!

Tech Focus: Honda Teams Haven’t Run Smaller Endplates on Flaps


Through just two races of the season, IndyCar teams are still figuring out what works and what doesn’t with their aero kits. Honda, after being outpaced in most of the practice sessions, were able to claim their first win via a lucky/good (depending on how you look at it) strategy call by James Hinchcliffe. 

One thing we’ve noticed so far is that none of the Honda teams have elected to run the inner, smaller endplate which is visible on the stock aero kit rendering in the red box (upper right). This element has been left off throughout all sessions by every team. The current design teams are using is highlighted via a red arrow above. 

The endplate itself is used to decrease drag by controlling how the air comes off of the wing and directing it along the wing tip vortices. This reduces disturbance in the air that would be created by “dirty air” that is not streamlined coming off of the car. The endplate also helps direct air around other parts of the car which is particularly important in front of the tire. A clean air-stream can increase car performance greatly.


With the flap setup covering the entirety of the tire (directing the airflow around the tire), the performance that would be gained by using the endplate was decided not to be beneficial to the teams thus far. They have managed to control the air wash to their liking without it. 

Another picture of the endplate:

Aero Kit Tech to Watch For This Weekend


With IndyCar heading to New Orleans this weekend for the Indy Grand Prix of Louisiana, there’s a few things to watch for in terms of aero kit development.

Structural Improvements
The opening round at St. Petersburg was a carnage filled race. Aero kit bits and pieces littered the track throughout most of the race, mainly the rear bumper pods and front wing elements. By one count, as many as 12 front wings were lost or damaged during the race. This can cause some unsafe conditions for drivers and spectators, too; Gabby Chaves’ bumper pod flew off of his car and hit a spectator around turn ten. Part of the reason for this is of course the track itself; St. Petersburg is a small and tight circuit that features lots of contact every year, similar to Long Beach. NOLA Motorsports Park is a lot wider, 40-50 feet in most places, and there shouldn’t be as much contact there. Even so, in order to combat future debris filled races, IndyCar has mandated that both Chevy and Honda issue “structural upgrades to strengthen designated . . . bodywork components.”

These components will be approved by IndyCar and debuted at the Indy Grand Prix of Louisiana this weekend. The exact way the two manufacturers will go about making these changes isn’t known yet, but we will get a look at it during Friday practice sessions. From the reports, it sounds as if no new parts will be added to the cars or kits themselves, just a reinforcement of the parts currently on the car. This seems the most likely path as the manufacturers won’t gain a competitive advantage by adding new parts or changing the current ones. We may not be able to notice a lot of these changes if they are material or structural, but new parts would be evident throughout practice. Look out for this increased strength during the race if the drivers start making contact with each other.

Extra Downforce For Rain
Rain is forecast for Friday, Saturday, and Sunday in New Orleans. Both Honda and Chevy’s aero kits have close to 200 parts on them, and a large number of them can be tinkered with and changed by the teams and drivers. If wet weather conditions do prevail this weekend, it will be interesting to see how the teams adapt their kits. The need for more downforce and traction on the wet track will have to be met by the teams. Look out for larger wings and flaps in order to increase the downforce on the car. If the race turns out to be a dry one (Sunday currently has a 50 percent chance of rain according to RaceCastWx), teams who choose an ultra-wet setup could be left behind. It will be a delicate balance that the teams will have to find. Watch out for it this weekend.

It’ll be the first true wet conditions that teams will have to run in. The second practice session in St. Petersburg was a wet session but no teams chose to run in it due to fear for the fragile cars.

Photo Credit: IndyCar/PR