What does gas flow a cylinder head mean?

“Gas flowing” involves re-profiling of the inlet and exhaust ports in the cylinder head to allow the fuel/air mix to flow in and the exhaust gases to flow out more efficiently.

What are cylinder head dowels?

Dowel pins are an often overlooked item when performing a rebuild or upgrading cylinder heads. Dowel pins keep gaskets in position and properly align cylinder heads to the engine block.

How do you gas flow a head?

The bigger the explosion, the more the downward force and the result is “More Power”. After the combustion stroke has taken place, the burnt gas exits the chamber past the exhaust valve and through the exhaust port into the exhaust system. This entire process is enhanced when the cylinder head has been gas-flowed.

Are cylinder head dowels important?

The dowels are there to properly index the head gaskets and the heads to the engine block. Your asking for possible head gasket problems and water or vacuum leaks at the intake if you don’t use them.

How does gas flow into the cylinder head?

After that, the next stage is to have the cylinder head ‘gas flowed’ – in other words, reprofile the inlet and exhaust ports in the cylinder head to allow the fuel/air mix to flow in and exhaust gases flow out more efficiently. One thing you can’t get away from is having the valve stems poking through the ports and interrupting gas flow.

When did gas flow cylinder heads become popular?

In the early eighties, modified or gasflowed / big valve cylinder heads were only ever found on racing cars. Today gasflowed / big valve cylinder heads have become very popular, given the current fuel pricing and huge gap in price between the top and middle of the range models, to enhance the power output of almost any modern vehicle.

Why is the inlet port of a cylinder head important?

The inlet port of a head has a single job – to allow the passage of fuel/air mix from the fuel injectors at one end to the inlet valve at the other, through which it passes to the cylinder. In order to do this as smoothly and efficiently as possible, inlet ports need to be as straight and obstacle free as the design of the engine allows.

How is gas flow measured on a head?

The larger the engine capacity the bigger the benefit of gas flowing the head as more air is moving around. Gas flow is measured on a flow bench and as the head is worked it is remeasured. A professional will get a feel for the type of channels that need to be made inside the head.