what are valves for?

Question

when your cars says 16v or 3v what does that mean and what do they do? What is thebest type?

Answer 1

Traditionally, internal combustion engines have had two valves per cylinder: an intake valve and an exhaust valve. These two valves are opened and closed by the rotating cam shaft which is coupled to the crank shaft. The intake valve opens during the intake stroke, when the piston moves down and sucks in a charge of air and fuel. The intake valve closes, the pistion moves up, compressing the mixture, then BANG! the spark plug fires, igniting the mixture. The hot gases expand, pushing the piston back down in the power stroke. Then the cam shaft opens up the exhaust valve as engine momentum pushes the piston back up, pushing the exhaust gases out of the cylinder. Then the exhaust valve closes, the intake valve opens, and the four-stroke cycle repeats.

An engine that has four valves per cylinder has two intake valves and two exhaust valves. The purpose of that is to allow intake and exhaust gases to move through the engine with less resistance, thereby increasing horsepower. An engine that has three valves per cylinder has one large intake valve and two smaller exhaust valves.

Answer 2

Well a valve has 2 functions: allow something in or out, or to seal something off.

In a vehicle engine there are two types of valves: intake valves and exhaust valves.

Now, think of an engine as a giant air pump, much like the pump you've used on your bicycle. An engine takes air in, burrns it, and then exhausts the resulting air out. The burning takes place in a compression chamber.

Let's consider the intake valve first. It opens to allow air to enter the combution chamber, then closes to seal off the chamber so that compression and burning of the air and fuel can take place.

As for the exhaust valve, it is closed during the compression and burning of the air and fuel, and then opens to let the resulting spent air out.

Hopefully you now understand the function of the valves. They. open close and seal.

Now the more valves you can use to open, close and seal, the quicker the combustion process can take place, which means a more efficient engine. Also, the more air you can get into a chamber with an intake valve, the more horsepower.

Also, one big intake valve can get air into a chamber more efficiently that 2 smaller ones. That's why some truck engines that used to be 2 valve (1 intake and 1 exhaust) have moved to 3 valves (1 huge intake and 2 exhaust).

Hope this helps.

Answer 3

Valves allow the air/fuel mixture into the combustion chamber, trap it for the combustion cycle and then allow the burned gasses to escape into the exhaust system. The more of them the cylinder has the more efficient this process can be. Using your example a 16 Valve four cylinder engine has two intake and two exhaust valves per cylinder. This is about the maximum because of space. A 3V would have either two intake and one exhaust valve per cylinder or the opposite. This is slightly less efficient.

Answer 4

A valve is the air input/output of your engine, egnition needs fuel and air (input) to make an explosion and then a way to get away the smoke (output) so each cylinder needs two valve's.

If you have more than two valve's on each cylinder then the input:output is faster and the engine reacts faster so more power and speed!

4 cylinders with 16 valve's is fastyer than 4 cylinder engine with 8 valves.

Engine with 3 valve's is in my opinion not available.

Is this what you are loocking for or is it me who is stupid.

Answer 5

Well I assume you know what a valve is....so you'll under stand what I will explain....valves are gate way doors in reality.... Intake valves...they let air in, and on some type of Eng.'s they let air and fuel into the cylinder cavity....trapping it for a combustion... then opens the Exhaust Valves to let the burned air and gas escape(or scavenging) to the exhaust system by the exhaust stroke of the eng.....the design of the eng. determines the amount of Intake and Exhaust Valves it might have...Most valves (intake and exhaust) on Eng.'s to day are carried in a Unit called a Cylinder Head...but in rare cases and in older Eng.'s called flat head series of Eng.'s the valves is designed the block of the Eng.but works on the same princable...

Answer 6

valves draw in the fuel into the cylinder and push out the exhaust from the engine (on fuel injection you only have exhaust). If you have a four cylinder 16v means 4 valves per cylinder. 3v means 3 valves per cylinder. the more valve the better the air flow. more air flow means more horse power. more valves per cylinder is best.

Answer 7

SAY WHAT, YES_ITS_M...
A Detroit Diesel is internal combustion and it doesn't have any intake valves.
And Yamaha was rolling with 5 valves per hole for many years.
Better skip your answer also.

Answer 8

well,you got intake and exhaust valves.when 1 is closed the other is open.they control the intake and exhaust.if you got a 16 valve,it means you got more power.

Answer 9

try this link

http://en.wikipedia.org/wiki/Multi-valve