On first inspection, steel seems like an unlikely material to use for a cylinder liners. Its density is almost three times that of aluminium, its thermal expansion coefficient is much lower than that of the aluminium piston that runs inside it, and it has low thermal conductivity. However, many people use it for liners, and it can offer the lowest total engine mass, despite its density. The real advantages of steel are its strength and stiffness. Aluminium cylinder liners are very popular,...
The pursuit of power in fixed-capacity, naturally aspirated engines has generally driven designers and engineers to increase engine speed. Simply put, engine capacity will dictate maximum torque (making some important assumptions), and the product of torque and speed equals power. There are several limits on increasing engine speed, but one of those against which engineers continually find themselves battling is the valvetrain, and in particular being able to keep the valvetrain under...
Despite some significant advances in polymer and composite materials in recent decades, race engines remain stubbornly metallic. While Formula One transmissions have embraced composite materials in their main cases, a combination of regulation and experience has deterred engine design engineers from using anything other than metals for most applications. We use a number of different metals as a matter of routine. Pistons are almost always made from aluminium, crankshafts are normally made...
It sounds too good to be true doesn’t it – more power and a lower-drag car, simply by using a bit of titanium. It won’t make you more attractive to the opposite sex, but titanium can do something for your success. Titanium alloys are most often used for their combination of strength and low density, or for their temperature resistance. As a material for cyclically loaded fasteners, their combination of high strength and low stiffness is useful. The property that makes...
There are many applications for high-strength steels in the modern racing powertrain. Their use allows us to make lighter parts and, given that race engine and transmission designers spend much time, effort and money on reducing mass, it should come as no surprise that they are so popular. There are some drawbacks with such materials though. As strength increases, it becomes more difficult to machine the component from the material in its hardened state. There are manufacturing processes...