Which Pneumatic Engine Rotates Better: Golden or Silver?

[@marcalfamick6516]

Bravo !!! très beau travail et merci d'en faire profiter les autres.

[@zaccapotatoes7130]

thats cool! what could these pneumatic engines be used for?

[@Posmetyev]

Thank you! This engines are souvenirs only. But I am planning to make small flying airplane based on the engine.