Roller rocker arm. The rocker are in the head that transfers the camshaft action to the valve. Opens and closes the valves. On a roller rocker, there is a small roller on the lifter end of the rocker arm. Some small gain in performance due to lack of friction. Very small. In a complete engine overhall where everything is done just right to improve performance, each little bit can have a combined affect that does improve the overall performance. Changing the rockers by themselves is not wort the expense.
If you have a 2001 or newer engine, it comes with roller lifters and roller rockers from the factory.
Chrome vanadium spring steel
If you are talking about suspension springs then your vehicle will sag depending on which side and the ride height will be lower than normal if it is an engine or brakes spring it depends on what spring it is i.e. (Valve spring, Throttle Body spring, Carburetor, Drive belt tensioner spring, Timing belt/chain adjuster spring,brake spring)
An engine valve normally needs to be removed from the head for a valve job, or to replace other parts related to its operation like the spring or valve guide. This is normally done when the engine has a poor seal from the valve/valve seat or oil consumption caused by the vavle guide.
If its the standard height, nothing. If they are screw in studs with tall nuts, then you will need tall valve covers.
Take off one of the valve covers, if the rocker has a roller tip on the side which it touches the valve spring then its a roller, if no roller tip is present then its a normal tappet rocker.
A valve spring "keeper" or AKA a valve spring "retainer" is used to lock a valve spring to the valve.
vale springs dependon what lift your cam is . need to know what lift cam it is where can get the correct pounds spring if not can have one BIG HEAD ACHE.
Valve pocketing is when a valve is hammering the valve seat.mostly due to miss adjusted valve spring/wrong valve spring/to strong of a valve spring or valve stem to short.Makes the valve seat deeper.
how many positions does a spring offset valve have
you need to compress the spring with a valve spring compressor tool, and then remove the valve keepers, and retainer.
The valve spring is the spring that closes the valve in the engine head after the cam lobe or rocker opens it . If the valve didn't close, many things would happen , the main one being the motor would not fire .
That would be a hydraulic roller tappet valve train.
The purpose of the valve spring is to maintain contact between the components in the valve train, so the valve motion will follow the cam profile.
Your engine will probably missfire and you will not have compression in the cylinder that has the broken valve spring because your valve will stay open.
Spring loaded safety valve.
pull a valve cover and look for roller rocker arms.