Racing engines often fail at high rotational speeds because mechanical springs are unable to retract the valves quickly enough to provide clearance for the piston.
Renault's pneumatic valve technology replaced steel springs with light weight compressed air bellows.
Additionally, the amount of seat tension required to keep a coil sprung valve under control results in greater peak lift loading.
Pneumatic systems sharing a common reservoir of pressure retain a more static level of force, controlling the valve effectively without any attendant peak lift load increase.
However, reliability and poor handling of their chassis kept the cars from success until 1989, when Renault provided Williams with a new V10 engine that began a winning streak.