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Deleted member 12676
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In "Advances in the Design of Two-Stroke, High Speed, Compression Ignition Engines" it is written that with a squish band there is more heat loss due to swirl. [which brings more burning fuel in contact with metal.] Heat is what causes expansion of gases to push against the piston so it equates to say that heat loss, without regard to other factors, reduces power. The advantage of swirl is better mixing and flame propagation. But in a small engine there is usually already enough mixing due to its high intake/transfer turbulence. When I tested a head on my 55cc that had a squish band the power output was less. This most probably is only the case for small engines since larger engines need help with fuel/air mixing, and flame speed increase is helpful because of larger distances from spark plug to cylinder wall.
This is not to say that a good cylinder head with a squish band will never improve power. There are always many factors at play in 2 strokes. Increasing the compression can give as much as a 5% boost in power. But it is my opinion that these small engines will do better without a squish band. I don't remember where I read that small engines have more intake/transfer turbulence but I did read it.
This is not to say that a good cylinder head with a squish band will never improve power. There are always many factors at play in 2 strokes. Increasing the compression can give as much as a 5% boost in power. But it is my opinion that these small engines will do better without a squish band. I don't remember where I read that small engines have more intake/transfer turbulence but I did read it.