Sometimes you want to make the car go faster. Powertrain’s job is to develop a package that best provides controllable power. The limits of the system are the inlet of the intake and the outlet of the exhaust. Included in between are the engine, its coolant system, fueling system, and transmission. Also critical to the powertrain subsystem is our dynamometer (dyno for short) which we use to develop, calibrate, and (ideally) test our package before it even gets on the car.
We currently run a Honda CBR600RR motorcycle engine. It’s a high revving, four cylinder that makes about 120 hp on the bike and 80 hp on our car. Per FSAE rules, our intake is heavily restricted - you can’t get as much air in the engine with which to blow up - so we run slower. Future improvements in our engine development and selection could mean bumping the power up on the four cylinder or losing weight by sourcing a smaller, less powerful engine.
What We Do
Parts for the car that we have developed in the past include:
Intake Manifolds: These deliver air through a throttle body, into a plenum (think “air reservoir”), through runners, and eventually to the engine.
Fuel Tank and Supporting Delivery: Fuel is delivered from a custom fuel tank through a pump, filter, regulator, and injectors.
Exhaust Manifold and Muffler: These parts move used air (emissions) through runners and expel that air via the muffler.
Radiator/Cooling System: Custom sourced radiator, fan, and coolant lines route water to cool our engine.
Oil Pan: Custom oil pan, holds oil while it is not slaving to keep our engine slick.
Other responsibilities of Powertrain:
ECU/Calibration: Fuel delivery, among other things, in most engines today is controlled by a computer. This computer must be told how much fuel to deliver and when. Ignition timing, throttle, traction control and anything else you could hook up to the engine through this computer can also be controlled.
Keeping the dyno running: Prototype race engine stands engineered and built by students break down a lot!
Modeling and analysis: CFD (Computational Fluid Dynamics), FEA (Finite Element Analysis), and 1-D engine modeling are the biggest tools used, to different extents.
In recent years, the team attempted a single cylinder with a turbo, which yielded no success. Subsequently, a four cylinder was implemented. Unfortunately, it ran one cylinder short during competition. Eventually, after much trial and error, powertrain found success with four cylinders. Engines have been tuned through varying the intake and exhaust runner lengths. Testing has proved promising, but more is needed.
Power is delivered through a Honda CBR600RR engine with custom cam and crank reluctor wheels. Oil is held in a 2-quart, low profile oil pan. Air is delivered through an electronic throttle body into a custom intake manifold. The intake manifold includes a 20 mm restrictor, 3.6 liter plenum, and 8 inch long runners. Air is exhausted through a 4-1 header with 32-inch runners and custom muffler. The engine is controlled by a Bosch MS6.2 ECU and is equipped with a rear mount radiator and 1.9 gallon fuel tank to deliver coolant and fuel, respectively.
Future Goals and Projects
Powertrain is currently focused on developing knowledge and validating the parts we have. This includes testing parts on the dyno, developing our engine calibrations, and creating models to optimize new parts. Projects to support these goals include engineering an engine test stand, engineering a fuel bench, implementing cylinder pressure sensing, and much more.