Igneous Rock is formed when a magma cools underground and crystallizes or when it erupts unto the surface of the ground, cools and crystallizes. Magma that erupts onto the surface is called lava. When magma cools slowly underground the crystals are large enough to see.
Readings for compression tests usually vary between 175 to 250 PSI (Pounds per Square Inch). A higher reading generally indicates better engine performance; however you should check your vehicle manual to find out what the ideal reading should be for your vehicle.
Pressure testing of a 2-stroke engine is a test performed on the engine to be sure that it has no air leaks. An air leak in a 2-stroke engine will cause a lean condition in the engines air/fuel mixture.ressure testing of a 2-stroke engine is a test performed on the engine to be sure that it has no air leaks. An air leak in a 2-stroke engine will cause a lean condition in the engines air/fuel mixture.