The Investigation on cam–follower contact is one of the most complex lubricated non-conformal contact due to its continuous variation of load, speed, and geometry. The complexity of the phenomena occurring in the camshaft systems makes experimental verifications very important. In this study, an already existing versatile experimental apparatus for the investigation of non-conformal lubricated contacts, able to measure film thickness using the optical interference method and friction force trough a load cell, has been modified in order to test cam–follower contacts. Some tests have been carried out for investigating the behaviour of some fundamental components of the rig. A theoretical/numerical simulation has been performed to investigate the dynamic behaviour of the system and in order to provide some indications for the interpretation of the experimental results. Purposely developed versions of the programme have been also an important support for the design of a new apparatus specifically addressed to the cam–follower contact with increased potentialities capable of more detailed measurements of film thickness and contact forces. The apparatus is able to reproduce a cam–follower mechanism that uses a rocker as a link device between the cam follower set and the valve.
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