I think the engine is of the interference type; if it was turning enough, there may be piston to valve contact issues.
On the m20, 50,000 is the interval.Firstly, you need to know if the car in question is cam timed by belt or chain. If so by belt, then yes at about 60,000 miles (100.000 km). If by chain, that is normally close to total engine service life.