5 Stroke Engine
The 4 stroke engine has been powering most automobiles in the world for many years, with only small changes being made over time to make the engines more powerful, more economic and efficient. There is now a new engine design that uses an extra stroke to help achieve these goals with smaller engines.
The engine has been developed by Ilmor Engineering and could be the future of design for automotive engines. The design uses 3 different cylinders to produce power, but only the outside two actually fire. The firing cylinders go through the normal procedure of intake, compression, combustion and exhaust to make their power. This is where the 5th stoke comes in, as the cylinder located in the center receives the exhaust gas from one of the outside cylinders and allows it to expand even more, creating power.
The outside cylinders alternate to keep pressure even across the board. The result of this additional step is a torque curve similar to a diesel while still being able to ignite from a spark plug and without the emissions associated with diesel fuel.
The engine is currently only 700cc but the power output of the running test engine is 130bhp with 122lb.ft of torque. Ilmor engineering state that when the engine is running perfectly the little 0.7 litre engine should produce around 150bhp, which is amazing for such a small engine.
I am personally very interested to see if this new 5 stroke engine manages to make it into a production car and to see if anyone will further develop the idea to make a bigger more powerful version.
5 Stroke Engine
5 Stroke Engine Cut-out
