The Exige already comes with a rear diffuser, but we replaced it with a larger and more effective Difflow diffuser. A diffuser uses the Bernoulli's principle where it increases the velocity of air underneath the car which decreases the pressure. The lower pressure under the car creates down force. The diffuser also reduces turbulence and drag in the car’s wake by acting as an expansion chamber for the air underneath the car to rejoin the high pressure ambient air. The extra vertical “fences” help guide the airflow and maximize it’s efficiency.
GRP Side Skirts
The GRP carbon fiber side skirts were also installed. In theory, they should help with the aerodynamics by preventing leakage of high pressure air from getting underneath the car from the sides. Plus, they just look good!
May 28, 2019
Although there is some weight to be saved by removing the trunk, the main purpose was to free up engine bay space, making it easier to work on. Secondly, removing the turn signal lights and adding grill mesh allows the heat from the engine bay to escape through the rear of the clam. The extra space will also allow me to mount a water-to-air charge cooler away from the hot engine in the future.
June 22, 2019
About six months ago, we ordered a Voltex rear wing and we finally received it, just in time for Laguna Seca! To help reinforce the rear clam, we installed Reverie’s carbon supports. They didn’t quite line up perfectly with the wing mounts since they were designed for the Reverie wing, but the area supported is enough to prevent the clam from caving in.
The RE71Rs were worn out, so we switched over to Hankook Z214 medium compound tires. It’s still a DOT (street legal) tire and not considered a true racing slick, but still a very good tire. This is the most simple change, but will have the biggest impact in the car’s performance.
Laguna Seca w/GGLC
June 24, 2019
On Monday, June 24, we decided to take a team day-off to go to the track with Golden Gate Lotus Club. In addition to drives, meets, and fun outings, GGLC hosts great track & autocross events. Only three run groups, so you get SEVEN sessions! Not to mention, they always offer snacks, coffee, fruits, and sometimes even lunch!
The first session was extremely foggy and visibility was poor, so we were under a yellow flag (no passing) for pretty much the entire session. I was only doing 1:50 laps, but I could already tell that the car was going to be much faster with the new tires and wing.
By the second session, the sun came out and it actually got pretty warm. I was able to push the car more to find the new limit. Not only did I notice the cornering grip was significantly better, but I could also brake much later and harder with the extra grip of the tires.
The wing really settles the rear end down even on lower speed corners like Turn 2, but where I felt it the most was through 4, 5, and 9. It was hard getting used to the fact that the faster I went, the more grip the car had.
The car ran well the entire day and I managed to clock a 1:39.5 lap from my previous 1:43.1. We will need to increase the spring rates a little bit to compensate for the additional down force. The car currently has pretty soft springs (450/600lbs).
Thanks Jim at Ravenol for stopping by to show support!
Here is the best lap of the day. Sorry, the exposure set on the Smarty Cam wasn’t set up correctly, so the video quality is poor.
Here’s a video of our good customer, AJ, in his supercharged S2000 following me. His car was having some overheating/bogging issues as well as some transmission problems, but still managed a 1:43 (2 seconds off his normal pace). He will be back at Laguna later this week hoping to do a sub 1:40 lap before bringing it back for a gearbox rebuild. Good luck AJ!