Generally, the more valves an engine has the more efficient it is.
Depending on which engine you have and if the engine is a dohc engine four cylinder engines have two valves per cylinder totaling eight, unless it is a dohc then it has four valves per cylinder then it would have sixteen, the same holds true for the six cylinder engines with single cam engines having twelve and duel overhead cam engines having twenty four
As any 4 stroke engines, it depends on the amount of cylinders it has although it is commonly said that "2 stroke engines do not have valves", this saying mainly applies to out boards, weed eaters and these types of engine, but some GM engines such as the 671s and some others do carry valves.
In many cars YES, but not all cars.The engines will be "Interference Engines" or "Noninterference engines"When the belt breaks in interference engines the valves strike the pistons and bend.
Pneumatic valves are used to close valves in high-speed internal combustion engines, pneumatic valves are mostly to help racing engines to get to high speeds.
On a standard V12 it has 24 valves however some newer engines have 3 or 4 valves per cylinder making the number 36 or 48.
The camshaft.
how to adjust valves on a 1050 kohler engines
For D7F 8 valve engines: Intake valves - 0.10mm, Exhaust valves - 0.20mm
Sixteen valves is always a 4 Cyl (4 valves per Cyl)
Some two stroke engines have 4 valves, Detroit Diesel 71 series and 53 series engines for example. Most small 2 stroke engines have no "Valves" at all in the sense of the "POP" valve used in four stroke engines. Some people feel these engine has one valve because the piston acts as the valve covering the ports cut into the cylinder walls.
Two per cylinder, for a total of sixteen.
On some engines the cam-shaft does not directly operate the valves, but uses a lever (the Cam Follower) to transmit the force from the cam to the valve. Basically they are levers, and they are used to open the valves.