Restoration cylinder head work question

[Gambitt]

I have a set of 186 heads I just dropped off at the machine shop to be machined as an original set of DZ heads were, with the big valves and all...my question is this, what type of valve guides are everyone using in these heads? The K-liners, or the larger type? The machinest told me the K-liners were only good for 10 thousand miles so he doesn't use them...any advice on this?

[pickelnose]

I am a machinest.the K-Liners are junk.dont use them.use the .500 outside diameter cast iron replacement guide.a special drill and ream is used to drill out the old cast in guide and then the replacement is pressed in.if done right,they are just as good as original.