There are valves in the head of the motor. They open to let in air and exhaust out. There is a spring around each one that keeps them closed until the camshaft forces the valve open.
Edit: Another way to put it is that the valve spring's job is to close the valve once it's opened by the valve train. The stronger the spring, the quicker it closes the valve and the higher the RPM the engine can operate without 'floating' the valves. The tradeoff is that the stronger the spring, the harder it slams the valve against the seat, reducing each's useful lifetime.
Yes.. The combustion chambers are different
No. The valve springs can remain on the head when removing the head.
A valve spring compressor
The camshaft opens the valve via its Lobes, against the valve spring, to open. The valve springs closes the valve back.
Valve springs keep valves firmly seated in the socket.
The valve springs.
Valve springs
Valve springs are not torqued they have no bolts on them at all, they are held in place by keepers that fit into the notches on the end of the valves.
you need to compress the spring with a valve spring compressor tool, and then remove the valve keepers, and retainer.
It closes and keeps the VALVES shut when needed.
Under the valve cover where the valve springs are.
The function of springs in a combustion engine is to lift the weight of the valve and to keep valves closed.