Was going through a Catalog I received from Competition Products, and some of the heads have the option of being 'CNC machined' for $95 or something like that. What does it mean if something is CNC machined?

computer numerical control (CNC) they use a machine to match ports, runners and combustion chamber.

So is that worth $95?

Instead of someone porting the heads by hand and possibly having variations from one port to another, they have a computer program port every one exactly the same on a 5 or 6 axis mill.

Jeff

YES ITS WORTH IT!!

BE CAREFUL: "CNC Machined" is NOT THE SAME as "CNC Ported".

Any number of operations could be done by CNC, including such "normal" stuff as machining the deck surfaces, intake gasket surfaces, exhaust gasket surfaces, valve spring pockets...etc. Doesn't mean they carve the ports and combustion chambers.

Might want to ask CP just WHAT has been CNC "machined".

Now that I look, it says 'CNC Chambers'. What does this mean?

The chamber would be where the valve faces are. The head gasket side. That would imply that everything from the back of the valve to the intake manifold surface are "as cast" Theoretically, if they CNC'd the chambers, they should all be equal CC-wise and that is not a bad place to start.

Jeff

If you're looking at the Canfields with the CNC chamber option....YES!
I bought mine as cast and spent waaaaaay more time and effort getting my chambers right than I would have if I'd went with the CNC chambers. And the CNC chamber option helps airflow bigtime.

Randy