This paper shows how the ITEA2 research project TIMMO has chosen to model timing constraints for delays and for synchronization in an unambiguous way. The shown timing model is valid even in systems where jitter and over- and under-sampling appears. These timing constraints can be used to model timing by augmenting both the AUTOSAR and EAST-ADL2 languages. The unambiguous semantics enables the use of timing models for building safety cases and for precise communication between different parties involved in safety-critical automotive applications.