The reactor model is a model of computation for concurrent systems that includes semantics for time to guarantee deterministic execution of events. However, the guarantee of determinism comes at the price of raising the complexity of building a runtime scheduling algorithm that efficiently exploit parallelism of real time systems. In this paper we propose a methodology called 'timing enclaves' for partitioning of reactor programs written using Lingua Franca, a novel coordination language that implements the reactor model. Timing enclaves decouple the timeline of an application to use multiple schedulers that allow parallel computation while preserving determinism. We evaluate our approach on a baseband processing benchmark, a complex use case with a high degree of parallelism and real-time constraints. We show that our approach has performance comparable to a prior asynchronous and nondeterministic implementation while ensuring determinism.