The Porsche swivel feet adjusters and Chromolly push-rods let you set the valves to zero lash (no play).  Stock aluminum push-rods are setup loose and expand at temperature.  Regular rocker tappets wear.  This mod requires the rocker arms from a 1.7 liter motor or aftermarket rockers.  To use the 1.7 rocker arms, it is necessary to clearance these with a grinder to about 0.40" total when done.  

 

You'll need to shim the mounting towers to use stainless steel / Chromolly pushrods.  That means you need an adjustable pushrod to work on it and you need the shims to get you the sweet spot where the valve is 50% below ad 50% above the mid point for proper wear.  Lots of information on line from Jake Raby and Ian Carr, etc.  It did not take long to do it.  The pushrods were ordered and then cut by a local speed shop that also pressed the pushrod ends into the cut rods for me.

 

I had to purchase an adjustable (dummy) push-rod and shims to calculate the correct total length for the Chromolly push-rods.  A machine shop cut them all for me and pressed-in the rounded ends.

 

All of this can reduce valve adjustment maintenance by up to 50%.  For now, I am running a header and have no heat and that makes valve adjustments easy.  Once you have heat exchangers and the air guides, the maintenance to adjust valves is more interesting.  If I add heat exchangers, then I'm stretching-out a chore interval.  Reduced wear means more consistent performance.

 

 

Blurry view of a substituted swivel foot adjuster (top right):

 

Expensive Porsche swivel foot at top and the stock one below it.  The swivel head needs more space to exist and move, requiring the rocker arm to be thinner to compensate for the increased length:

 

The 1.7 liter motor rocker at left, the stock 2.0 rocker at right.  You can see the 90 degree grinder left some small marks, but this is not the mating surface just the rocker arm thread surface.  A machine shop could do these with a nicer facing, but the grinder was fast and almost free to do the same job.  Note the minor radius of the edges to prevent finger cuts.  Everything was sanded-out with Emory Cloth and then cleaned twice before assembly.

 

 

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