5/31/2018 2:23:00 PM CLHS earns top honors in modified class during supermileage competition at BIR
The CLHS Supermileage Team competed in the 30th annual Minnesota Technology and Engineering Educators Association Supermileage Competition May 14 and 15 at Brainerd International Raceway. This is the 29th year that advisor Mike Sandell had brought a group of students to the competition.
This year the team entered three vehicles in the competition. Two were entered in the Modified class and the third in the Stock class. This was the second trip for all three vehicles. Two had undergone some major structural changes in preparation for this years competition, while the third had just fine tuned the drive system and worked on carburetor jetting to increase the efficiency of the Briggs and Stratton engine.
The purpose of the competition is for teams of students to design and build a vehicle engineered to get the highest “mileage rating” possible. The competition is held on the BIR three mile road course. A competition run is two laps. The teams are given a fuel bottle that is weighed to the hundredth of a gram both before and after the mileage run. A good run will use less than 15 grams of fuel, resulting in a mileage rating in excess of 450 mpg. For the competition, winners are based on an average of the top six completed mileage runs.
Car 3, the Stock Class vehicle, was a very consistent competitor, completing 17 of 20 mileage attempts, setting a team record for most runs attempted/completed for CLHS. In preparation for the competition, the students rebuilt the drive train that enabled this type of performance. This car had a high single run of 410.75 mpg and a competition average of 385.34 mpg. These results were good for a 4th place finish in the stock class. This was a team of students new to the competition, which will be returning next year with some great experience to help improve their results.
Car 5 is one of the Modified class entries. This vehicle was carbureted and the team worked to refine the drive system and use smaller jets to limit the amount of fuel used in combustion. This “trick” had been used by previous teams, and had been passed down in notes taken after each competition. Adjusting the carburetor after changing the jets had this vehicle running “lean and mean”, just what was needed to do well. The vehicle came home with the first place trophy for the modified class. While not having the highest single run only being able to reach 460.08, it was a very consistent runner. The competition average was 414.49 mpg, the other five runs of the average were between 380 and 432 mpg.
Car 44 was the second vehicle CLHS entered in the Modified class. This vehicle has a fuel injection system purchased with a donation from the Chisago City Fire Department for the 2017 competition. The vehicle was unable to complete six runs in 2017 due to issues dialing in the fuel injection system. The team worked to get the system running constantly in preparations for the 2018 competition.
Going into the competition, they felt that they had found all of the “Gremlins” that had plagued them last year. A blown fuel line in their first mileage run attempt showed that they hadn’t found them all. The team completed 7 of 12 mileage attempts. One of the best mileage runs was not completed in the allowed 24 minute period, going over by 77 second. This resulted in a 770 mpg penalty, resulting in a lost mileage run.
The other 6 runs ranged from 42 mpg to 419 mpg. Had they been able to repeat the results of the top 3 of their runs, they would have been in the trophy hunt. However, having issues with the vehicle's fuel delivery system on day one and clutch issues on day 2 kept the vehicle in the pits more than on the track. The team has identified a couple of issues to work on for next year and believe the third year may be the charm for this vehicle. “Success of this program is not only due to support form Chisago lakes schools, but from the community as well” said Sandell. We are fortunate that we are able to have support from many of the students after they have graduated over the years. Once again use of a enclosed trailer to transport the vehicles, parts and tools was provided by the Addyman family.
“Parental support for the program has been great with Kevin and Kris Drewlow providing a grilled chicken lunch.
As mentioned above, Chisago City Fire made a financial donation to the group the past two years and there are many other local businesses that have either financial support or material goods and parts for our program. Thank you to all who have supported this program!”