Smoothing/radiusing sharp edges on aftermarket pistons

[stownsen914]

What’s the current thinking on smoothing/radiusing edges on aftermarket pistons like JE and CP? Seems like it makes sense to at least knock off the sharp edges around the valve pockets. How far do folks take this? My application is a track engine 12:1 compression.

A couple threads I found on the topic:
https://forums.pelicanparts.com/911-engine-rebuilding-forum/452068-sharp-edges-je-pistons.html
https://forums.pelicanparts.com/911-engine-rebuilding-forum/368320-jugs-slugs-confessions-je-piston-owner.html

[manbridge 74]

Using cams with any overlap? Then I’d certainly follow Henry’s advice in the second thread you listed.

[icarp]

For the same reason for attending to the spark plug hole and threads.
The sharp edges can be a tremendous hot spot in the combustion chamber.
It is paramount to mitigate all possible hot spots , Then you can rely on the twin plug to do it's job reliably and consistently . Attend to ALL SHARP EDGES.
Just my thoughts
Ian

[TimT]

Debur the valve pockets, and massage the top of the valve pockets at the piston crown.



or you can use a dremel or die grinder..