The combustion chamber is the business end of the internal combustion chamber. Inside an internal combustion engine, the combustion chamber is the place where the air/fuel mixture is delivered, compressed and ignited. The air/fuel mixture, once it has ignited, produces an explosion which forces the pistons to carry through another cycle. This combustion chamber cycle is often referred to as the “suck, squeeze, bang, blow” cycle (and I’ll leave it to your imagination to find a colourful way of remembering that process…).

The actual size of the combustion chamber is the volume left clear of the cylinder head when both the intake valve and the exhaust valve are closed, and the piston is at the top of its cycle. A smaller combustion chamber produces a higher compression ratio and hence will produce more power. Higher compression also created higher temperatures.

The size of the combustion chamber can be changed either by boring the cylinder head or by changing the shape of the piston head.

We hope that helps answer the question ‘What is What is a Combustion Chamber?’!

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