Gti6 Head Question

[Paul_13 212 1 Cars]

Hi just a quick question, we'll be taking my mates head off his gti6 engine (105k on clock) to do stem seals.

Its got good compression across all cylinders and has never overheated.

 

Is it compulsory to have a skim?

We will check the flatness of the head using a rule feeler guages etc, but was thinking of leaving valves in places incase the guide gets damaged taking them out.

 

Thoughts?

[welshpug 1,657]

it can still be a bit warped without "overheating"

 

might as well check the valves seeing as the springs are coming off, you wont damage the guides unless the stems have mushroomed which afgaik is more common on the MI16.

 

make sure only the minimum is removed, or you'll have valve-piston clearance issues.

[Paul_13 212 1 Cars]

you wont damage the guides unless the stems have mushroomed which afgaik is more common on the MI16.

 

make sure only the minimum is removed, or you'll have valve-piston clearance issues.

 

Thats what i was getting at with the mushrooming.

 

You can still have a hefty skim and not have problems and that is coming from Miles who has has years of experience.

[welshpug 1,657]

depends what you call a hefty skim...

 

I'm going from Sandy's experience of these heads and looking over them myself.

 

you'll soon find out if the valve stem is damaged as they wont just drop out.

[Anthony 1,003]

With standard cams timed up as standard, yes, you can get away with a reasonable skim and still use a standard thickness HG.

 

Longer duration cams or the originals timed up with more advance however, and you're already very tight on valve clearance on an unskimmed head.

 

As has been said, even though it's not been overheated, the head will still need to be properly checked - false economy not to frankly.