Hello SuperMileage viewers, for the month of February we wanted to talk to you about the engine for the gasoline prototype. Last season a senior design team was able to build a custom head for the engine featuring an increased compression ratio and including dual spark, larger valves, and variable valve and ignition timing. However, the reliability and functionality of the engine left much to be desired. This season’s modifications began with an addition of a throttle body that uses a butterfly valve to regulate air flow entering the engine. The reason this was implemented was because the ability to adjust the idling speed of the engine at lower speeds was increased, and the engine can now be run at midrange speeds which will allow for a much smoother transition when accelerating from idle to W.O.T. To make testing easier, we made multiple wire harnesses to make testing more mobile. This is so the engine can be taken to the dyno room to run tests without having to take the entire vehicle.
The engine was tuned at a variety of speeds and loads in an effort to reach the stoichiometric air fuel ratio within the engine for the most efficient combustion. A well-tuned engine and fuel map are essential to performing well and reliably at competition. The strategy that the team is using incorporates short “burns” times at which the engine is running, and long coasts where the engine is completely turned off. It is essential that the engine make the most power possible for the burn portion of the race. The best performance for us is to have the highest power with the lowest fuel consumption. Although we have started testing with the engine, there is still a lot of testing ahead of us and we have a lot of hard work that needs to be done To make the engine work properly with the drivetrain. In order to accommodate that need the engine will be road tested and also chassis dynamometer tested. Make sure you guys keep your eyes out for more updates that are coming up ahead.