whats the normal clearance between valve guide and stem for the OEM 930 wastegate?

[fredmeister]

This is a turbo specific part but thought guys on this forum might know the answer to this question:

What is considered a normal clearance between the valve stem and the valve guide bore for an OEM 930 turbo wastegate?
I can here air blowing past the valve guide and into the exhaust port when I pressure test the wastegate housing. I realize a small amount of air will inevitably pass thru the clearance gap bewtween the 2 parts, but when is it time to replace the valve guide from wear? I have not been able to find a spec on this yet. Would like this info in order to be able to machine a new guide and have it pressed into the housing if need be.

Air leaking past the guide is air lost to opening the wastegate valve so ideally this should be a minimum.

Appreciate any info,
Fred

[ivanuf]

Anyone has some answers to this old post?

[racing97]

I would assume it would be no more that a exhaust valve guide which is .0022 thou

regards

[Steve@Rennsport]

Originally Posted by racing97

I would assume it would be no more that an exhaust valve guide which is .0022 thou

regards

Exhaust valve guide clearance should never exceed .007".

.022" is FAR too much.

[racing97]

.0022 is two thousands and two tenths a little less than .007 aye....

regards

[reclino]

I did a quick search of the forum. Came up with this.
http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/748196-overboost-problem-solved.html