Unfortunately I thought was a blown head gasket has turned out to be a lot worse.
I have a small hole in the head. It so small I can see it.
 
Its a hole that is common to the exhaust port the combustion chamber and the water gallery. almost like the porting has been opened up too much or the head has porosity.
 
Is this a common problem ? And can it be fixed ?
 
Cheers
Fahley

Porosity is very common/normal in cast aluminium and cast iron.
 
In automotive only causes problems when the porosity allows liquids or gases to go places they are not supposed to go.
 
A good head repair company will apply a dye and grind out the porosity line and replace it with weld.
 
Nothing to be afraid of. Like most solutions to most problems will cost money though.

Cosworth cast components do not have porosity.
 
Cosworth is the grand daddy of modern casting techniques, being zircon sand and pressure cast roll over cores.
 
The head has either corrosion, been over ported or has suffered water cavitation leading to boiling leading erosion or a combination of the 3.
 
Anything can be fixed however if it's gone there how long before others go?
 
The head needs to be completely stripped and completely clean to even start making an assessment.