Chris,


Using a tuned-pipe on an engine designed to run with a normal muffler (and I would say over 99% of OS.32SX engines do run with the stock muffler, or a non-tuned replacement), will increase the eventual compression ratio, often beyond what is good for the engine.

The result is most often burnt-out glow-plugs, or a need to use a richer mixture setting, to retard the eventual ignition.
But over-heating and dead-sticks can also be an onset of this.


Adding a head shim (to the existing one), or using 5-10% less nitro in the fuel (if you use 15% use 5-10% nitro), would often solve this.
The bubbles in the fuel-line would further compound this issue, leaning the mixture and advancing the eventual ignition.


Remember - the fuel controls in a glow engine control the ignition timing.