Piston rings have small gaps that allow them to expand during engine operation. If these gaps line up, fuel and gases can escape into the crankcase, causing loss of power and increased oil consumption ...

Engine building is technically a science, but the truth is that there is just as much art as there is science. Where most might think that the “art” part of engine building is in the design and ...

Most of us consider piston rings little more than a necessary evil. That's probably because grinding rings is a time-consuming chore. And who hasn't accidently ground a gap too large and wasted both ...

First-time engine builders and those working on mass-produced powerplants commonly use off-the-shelf pregapped piston rings. However, high-performance engine builders seem to spend a lot of time ...

A new technique termed the "fixed sleeve" method has been developed to measure the instantaneous friction of the piston and ring assembly as a function of crank angle. This method is a derivative of ...

SAE Transactions, Vol. 96, Section 7: FUELS AND LUBRICANTS (1987), pp. 240-257 (18 pages) Extensive measurements of oil film temperature and mainly of friction losses have been performed on an ...

Tribological evaluation of the interaction between a piston ring and the cylinder liner is a key step toward understanding engine tribology. This kind of test helps automotive manufacturers to comply ...