Of all the components in a race engine, the top or compression ring has probably the hardest task. Although its primary purpose is to seal the combustion chamber from the crankcase below, this role is somewhat complicated by the requirement to dissipate the vast majority of the heat in the piston and to do so under the most trying of dynamic conditions. Positioned as close as possible to the top of the piston crown as is technically feasible, it is suggested that as much as 80% of the heat...
A piston can’t do a good job unless it has a good ring pack, and likewise, a good ring pack will be useless without a good piston. Most people will appreciate that the piston ring exists principally to reduce the amount of combustible gases escaping into the crankcase, but I’m afraid there is a lot more to it than that simple statement. To start off with, the seal has to move at a speed of something up to 5000 ft per minute (26 m/sec) and cope with piston temperatures of 300 deg...
Ever the innovator, NHRA Funny Car crew chief Austin Coil of John Force Racing is currently investigating the use of JFR-produced forged steel ring land inserts on the Venolia pistons used on 14-time Funny Car John Force’s Ford Mustang. “It is a lot like units that the diesel pistons have and the approach was used very successfully in the turbocharged Honda Formula One cars, back in Ayrton Senna’s day,” Coil told us. “But since we can’t afford a million...
The piston lives at the interface of two hostile environments. One dominated by extreme temperature and pressure, and the other by inertia, kinetic energy and friction.Piston development is an unceasing challenge for the powertrain engineer and the tools of his trade are to be found in many diverse areas, spanning a whole gamut of bespoke materials, advanced tribological solutions, surface topography, treatments and finishes through to the ingenious oil cooling solutions found in modern...
The piston rings in an engine serve to act as a seal to prevent the escape of fresh inlet charge and combustion products into the crankcase, and also to prevent an excess of crankcase oil from reaching the combustion chamber. As such they are an important component to consider in engine design. Poorly performing rings can lead to poor engine performance and increased oil consumption.The general trend in piston ring design is towards lighter weight components and fewer of them. In...