Been soaking my pro 280 front pipe and mid box in caustic for last 48 hours .. I checked earlier and ice llike crystals are forming in pipe and carbon slightly loosening .. How long does this process usually take .. Any help very welcome

I never had any success with caustic soda. I used to throw the front pipe of my rev 3 on the fire outside. Burnt out all the carbon beutifully. Wouldn't risk it on my evo as the mid section is integral.

Crystals is the caustic freezing. Depending how strong the mixture (% by weight to water mixture) if above 30% It freezes at @ 8degC.