O.S. Engine OS4A407040 GGT10 Pulse Spacer Upgrade  [OS4A407040]

Precision pulse spacer for model engines

This O.S. Engine pulse spacer is a compact accessory positioned between the engine mount or exhaust flange and the manifold. Its purpose is to allow careful mechanical adjustment of pulse behaviour on glow and nitro R/C engines by shifting how pressure waves meet the intake and exhaust.

Fitting the spacer is a routine task for those experienced with engine installation: place it at the exhaust or mounting flange, fasten with the existing bolts, then confirm alignment and seal integrity. Only common hand tools such as hex drivers are normally needed, but always check flange condition and any gasket material before completing assembly.

By changing the arrival and strength of pressure pulses at the engine interfaces, the spacer can alter throttle response and affect the engine's tuning window. Introduce changes incrementally and record each test so you can quantify the spacer's tuning effects.