aaddpp

So I have a question about how to handle the piston ring edges when installing new rings. Some say to sand all the edges with 400 grit sandpaper, others I've spoken to just go after the edges at the gap with an emery board, and a piston I've been messing around with seems to have untouched ring edges. I can't find a 928 specific answer in search, so I wanted to see whats worked for others when replacing their rings - Goetze in this case if I go forward. To help simplify the descriptive process, I made up a 3-D image of a ring, with labels that can be referred to. BTW, label "A" includes the top and bottom edge, label "B" includes front and back edges

Thanks, Dave

BC

I was originally taught to just take down edge B a slight amount to round it off so as to not scratch the bores on assembly. Untouched otherwise, unless you need to cut the rings.

atb

I'd be interested to hear what the experts say. I think the OEM rings are made to such a tight tolerance that I'd be leary to mess with them. Not exactly the "file to fit" rings from your grandad's flathead ford.

GregBBRD

Install carefully into bore to confirm that you have ordered and received the correct rings. End gap will be small.

Install onto piston and install piston.

No sanding or files required.

aaddpp

Thanks guys. Taking down "B" seems to be really common practice, but it's good to know you can set everything up w/o modifying the ring edge here. Many thanks for the responses, Dave.