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Discussion Starter #1
Trying to get some specifications to match up on a 1Z head is proving confusing. The Bentley doesn't provide a spec for valve protrusion/recession relative to the head surface, should they protrude or be recessed, does it matter as long as the recession below the valve cover rail is at spec?

In order to get the measurement A, section 15a-18, figure 20 in Bentley the valves will end up being recessed in the head, currently all of them protrude to what seem like widely varying degrees (see picture).

For ex. on the farthest to the right, in order to get the valve cover rail to top of valve stem distance to be correct the valve will end up being recessed by .021" whereas it is currently is protruding by .019".

How is the preload for the lifter/cam measured after all this is done?

Any clarification is appreciated.

Tom
 

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Are the valve seats cut correctly? The lifters are hydraulic, just store them upside down and after installation, don't start the car for 1/2 hour. There's no other adjustment for the lifters.
 

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Discussion Starter #3
Getting ready to give it a valve job but want to make sure we aren't removing too much material. Ideally shouldn't all the protrusions be the same?

If we make the valve guide to tip of valve stem distance to spec they will all be recessed, I've only seen 2 1Z heads and they both had protruding valves.

Thx, Tom
 

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The pics I've seen also had protruding valves. Contact frank's vw tdi's at 417-232-4634 , he does a lot of TDI heads and could quickly answer any questions. Not sure myself.
 
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