What is overhead cam?

The camshafts have the job of opening the valves that let air into and exhaust out of the engine. The main benefit of dual overhead cams is that they allow an engine to have four valves per cylinder. Each camshaft operates two of the valves, one camshaft handles the intake valves, and one handles the exhaust valves.

What is the purpose of an overhead camshaft?

Overhead camshaft, commonly abbreviated to OHC, is a valvetrain configuration which places the camshaft of an internal combustion engine of the reciprocating type within the cylinder heads (“above” the pistons and combustion chambers) and drives the valves or lifters in a more direct manner compared with overhead …

What is overhead cam in motorcycle?

A DOHC engine, on the other hand, has one camshaft dedicated to intake and one for exhaust. “Overhead” here means that the camshaft is located on top of the valves and certainly on top of the engine block.

What is the difference between an overhead cam engine and pushrods?

Sometimes referred to as overhead valve (OHV) engines, pushrods use only one camshaft. Most pushrod engines use a timing chain to connect the crankshaft to the cam. The cam in a pushrod is located within the engine resulting in a lower center of gravity than the cam-on-top design of OHC engines.

What does DOHC mean in car engines?

DOHC Dual overhead cam engines
Dual overhead cam engines are found in most modern vehicles today. They allow better airflow with less obstruction and are generally much more efficient engines than OHV or SOHC engines. Two camshafts operate 4 valves per cylinder, one separate camshaft for intake and exhaust valves.

Is Twin Cam and DOHC the same?

Dual overhead camshaft (DOHC, also known as “twin-cam”.) engines have two camshafts per bank. The first production car to use an DOHC engine was built in 1910.

Why is dual overhead cam better?

Dual overhead cam engines are found in most modern vehicles today. They allow better airflow with less obstruction and are generally much more efficient engines than OHV or SOHC engines. Two camshafts operate 4 valves per cylinder, one separate camshaft for intake and exhaust valves.

Which is better SOHC or DOHC?

To sum it up, a 4 Valve per cylinder SOHC engine with a lighter valvetrain mass would have better performance characteristics at the lower end of the powerband. However, at higher engine speeds, a DOHC setup with its higher valvetrain mass and as many valves per cylinder will develop higher peak torque and horsepower.

Which is better single or dual overhead cam?

A DOHC, four valves per cylinder configuration allows better airflow at high engine speeds, resulting in better top end power. However, at higher engine speeds, a DOHC setup with its higher valvetrain mass and as many valves per cylinder will develop higher peak torque and horsepower.

What is the difference between overhead cam and overhead valve?

The term “OHV” stands for “overhead valve” and “OHC” stands for “overhead camshaft.” These terms actually describe the cylinder head layout of a piston engine. An overhead valve (OHV) cylinder head configuration is used in today’s modern-day engines where valves are arranged over the cylinders.

Are DOHC engines good?

A DOHC, four valves per cylinder configuration allows better airflow at high engine speeds, resulting in better top end power. DOHC engines also allow the spark plug to be placed right in the middle of the combustion chamber which in turn promotes efficient combustion.

What is difference between SOHC and DOHC engines?

If the engine has a single camshaft it’s called a SOHC (Single Overhead Camshaft) engine and if the engine has two camshafts it’s called DOHC (Double Overhead Camshaft) engine. Every engine, whether it’s air-cooled or liquid-cooled, needs camshafts, whose main purpose is to open the intake and exhaust valves.

What are the advantages of overhead cam?

It is shown that the principal advantage of overhead camshafts is the increased natural frequency of the valve train. The resulting improved dynamic characteristics of the valve-actuating mechanism make it possible to design camshaft profiles which expand the useful operating range of high-speed engines.

What does it mean when car has dual overhead cams?

Dual overhead cam engines are found in most modern vehicles today. They allow better airflow with less obstruction and are generally much more efficient engines than OHV or SOHC engines. Two camshafts operate 4 valves per cylinder, one separate camshaft for intake and exhaust valves.

How do you calculate Cam overlap?

There are a couple different ways to calculate the overlap of the cam. 1) The easiest way is to add the intake opening times to the exhaust closing time. Seat to seat times (advertised duration) must be used. .050″ durations or timings will not give the correct overlap.

What does overhead cam mean?

overhead cam (plural overhead cams) (automotive) A type of internal combustion engine design which has the inlet and exhaust valves in the cylinder head and has the camshaft(s) up above the valves too.