how to explain cavitation(sp)

i am having trouble explaining cavitation to a friend of mine. From what I understand, its when pressure decreases because a supercharger has met its limit with boost capabilities in its current mechanical state and negative pressure occurs.

I know this is not fully explaining this occurance, does anyone know of a better way to explain this :think:


sup man
i could be completely wrong but i thought cavitation had to do w/ liquids and fluids

If we were speaking about a water pump, cavitation is when the impeller is spun so fast that the water feeding it cant fill the spaces between the individual blades. This results in loss of head pressure, vibration, etc.

Apply the idea of the water pump to supercharger… i is when the super charger spins too fast exactly like you said LS/VTEC… remember, gases are fluids just like water…

here is a paragraph from this book i have…sounds similar to what ur saying

“Surge is where the air backs up in the compressor and oscillates violently back and forth in the compressor wheel. This happens when the engine’s swallowing capacity is exceeded by the compressor’s output, causing the air to back up in the intake tract. The mechanics of surge is when the pressure after the compressor exceeds the energy of the axial velocity component of the compressor wheel’s output, which causes the airflow in the compressor wheel to back up. The airflow backs up, the PRESSURE after the compressor DROPS and the airflow resumes…”

may not be the same thing ur talking about but i thought it sounded cool… this book has lotsa info.


good stuff


Surge is what happens when you have a restriction on the outlet side, not really related to cavitation. Blow-off valves are generally to prevent what it is you’re describing.