Two Companies Demonstrate Camless Engine

Camshafts and valve gear are the largest parasitic losses within an engine, and engineers
have sought for years to design a powerplant without them. Recently, through a joint effort
between Sturman Industries Inc. and AVL Powertrain Engineering Inc., significant benefits
have been demonstrated using Sturman’s camless engine and AVL’s combustion technologies.
According to the companies, using an experimental engine based on one cylinder of a high
volume 4.6-liter gasoline engine, the following results were attained: a 21 percent
improvement in fuel economy achieved by combining throttle-less operation and skip-firing
strategies, plus improved low-end torque and an emissions improvement consisting of a 20
percent to 92 percent reduction in oxides of nitrogen and reduced hydrocarbons. “These
results are significant in that they are targeted at an SUV application, and technically
they demonstrate that combustion doesn’t affect lift stability with our variable lift and
variable duration system. This is also enabling technology for HCCI combustion,” said Dan
Nehmer, project head for Sturman.