91أ¨دبةْ’s very own Team Carbonair competed at the 2024 Shell Eco-Marathon Americas—one of the world’s leading energy-efficiency engineering programs for students. The competition aims to push the boundaries of what is technically possible and provides a platform for teams to use their STEM skills to build their own ultra-energy-efficient cars and then take them out on the track in competition.

The Shell Eco-Marathon Americas competition was April 3-7, 2024 at the Indianapolis Motor Speedway. Team Carbonair participated in the Prototype Internal Combustion Engine (ICE) competition in which student teams design and build a single-cylinder vehicle that will yield the highest fuel economy measured in miles per gallon. The team has 11 members who worked on the vehicle this academic year. Seven students traveled to the competition:

• Harrison Crasko, mechanical engineering sophomore
• Karson Dimmitt, mechanical engineering senior
• Chris Imholte, mechanical engineering senior
• Sidney Lencki, mechanical engineering senior
• Aubry Nilsson, mechanical engineering freshman
• Charlotte Pyper, mechanical engineering sophomore
• Maclane Wightman, mechanical engineering sophomore

This was the first time in five years 91أ¨دبةْ participated in the Shell Eco-Marathon. The group, advised by Dr. Prabhakar Venkateswaran, vice chairperson of the Mechanical Engineering Department, achieved the goals they set for themselves: pass technical inspections and complete test runs at the competition. Unfortunately, they only completed 2 laps due to engine reliability issues. A full registered run is 4 laps (about 9.5 miles).

Team Carbonair Vehicle Facts

• Vehicle shell: Carbon fiber composite body (re-furbished from a previous year)
• Vehicle weight: 69 kg with a minimum turn radius of 8 meters
• Rear brakes: Fully custom hydraulic system where the pedal portion is a go-kart brake master cylinder and the hydraulic actuator is motorcycle slave cylinder, which then pushes on a lever to activate drum brakes on the rear wheel.
• Engine: A converted moped engine out of a GY6 with a displacement of 50 cubic centimeters. Originally carbureted similar to a lawn mower engine, it now has an electronic fuel injection system that the team set up and tuned to work.
• Drivetrain: Custom mechanical fuel pump which is a former electric chemical transfer fuel pump. The team directly drives the rotor of the motor from the crankshaft of the engine through a 5:1 gearbox. Since the rotor is being mechanically driven and not by electricity, it is considered a mechanical fuel pump even though it utilizes electromagnetism similar to an electric fuel pump.

“Unique to our drivetrain compared to other shell vehicles is that we built a custom mechanical fuel pump, whereas most teams utilize a pressurized fuel tank from an external reservoir,” said Chris Imholte, Team Carbonair engineering manager. “Our rear braking system was also very different from other teams which typically utilized just ATV or bike brake disc caliper systems (most of which are not custom parts or from different systems combined).”

At the event, the team worked 12-hour days fine tuning their vehicle, readying it for inspection, and solving last minute mechanical issues. Overall, the team had to overcome significant adversity to complete their goal, but they walked away with their heads held high and excited for the future. 

“Team Carbonair is committed to inclusion and we are proud of our members’ backgrounds,” said Imholte. “Many of our members did not know how wrenches, bolts, drills or other tools worked and gained this competency through working directly on the vehicle. Those who did were also welcome and able to contribute in a meaningful way. If you look at the make-up of our team, you’ll see a diverse team of empowered individuals. We take this as evidence that we are a welcoming and inclusive club on campus where everyone has inherent value with important contributions on the vehicle. Going to Indianapolis and competing has given further inspiration to the future of the vehicle and team, and we are excited to build upon the base that was set this year.”