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No two gauges read the same in the same cylinder.
The same gauge will give a different number the next day.
110 is not a bad number as long as all cylinders test the same more or less
Lets see ...
1 atmosphere of pressure is about 14.7 psi
You'll need to know the compression ratio for that engine to calculate the theoretical max pressure.
But a basic calc would be something like this...
given a 10 to 1 compression ratio per cylinder
10 x 14.7 = 147 psi
subtract 14.7 that being the existing air pressure outside the cylinder
147 - 14.7 = 132.3 psi difference between TDC and BDC
Which is a totally bogus answer! 4:49 pm
There is not a direct conversion from compression ratio to the psi measured with the gauge.
Got to thinking about it as it's a rainy day, and I realized that there are a lot more variables involved which I left out.
Like the pressure inside the 2 stroke crankcase that moves the air/fuel charge into the firing chamber.
And it's a dynamic system, with pressure changes taking place depending
on where the piston is in relation to the intake and exhaust ports.
What else can you do on a rainy day but read through mechanics and physics websites?
The same gauge will give a different number the next day.
110 is not a bad number as long as all cylinders test the same more or less
Lets see ...
1 atmosphere of pressure is about 14.7 psi
You'll need to know the compression ratio for that engine to calculate the theoretical max pressure.
But a basic calc would be something like this...
given a 10 to 1 compression ratio per cylinder
10 x 14.7 = 147 psi
subtract 14.7 that being the existing air pressure outside the cylinder
147 - 14.7 = 132.3 psi difference between TDC and BDC
Which is a totally bogus answer! 4:49 pm
There is not a direct conversion from compression ratio to the psi measured with the gauge.
Got to thinking about it as it's a rainy day, and I realized that there are a lot more variables involved which I left out.
Like the pressure inside the 2 stroke crankcase that moves the air/fuel charge into the firing chamber.
And it's a dynamic system, with pressure changes taking place depending
on where the piston is in relation to the intake and exhaust ports.
What else can you do on a rainy day but read through mechanics and physics websites?