Before installing the piston & cylinder, the piston rings need to have their gaps checked.  If the gaps are too small, the ring will bind in the cylinder when it heats up.  A gap that is too large may cause a bit of leakage, but a gap that is too small can destroy your engine.  Wiseco recommends gaps based on application.  For my application I chose “Street – Moderate Turbo/Nitrous”.  That seemed reasonable to me.  I could have selected “High – Performance Street/Strip” but I decided to be safe and give it that little extra gap.  For my selected application, the specified gap for the top ring is .0050” for inch of bore diameter.  With a 3.819” bore diameter that works out to .019” gap.  The specified gap for the second ring is .0055” per inch of bore diameter.  That works out to .021”.

Use a feeler gage to check the gap.  The ring must be positioned square in the bore.  I made this tool from an ABS pipe fitting.  It positions the ring exactly ½” down the bore and ensures the ring is square (1/2” down the bore at all points around the circumference of the ring).  The ring must be square to get an accurate measurement.

Then use feeler gages to check the gap.  I started with the second ring.  It was a bit tight.

Note how the butts are parallel.

Can you see any markings on the 2nd ring?  It’s there.  Be careful, it’s very difficult to see.

While on the subject of markings, see this arrow on the top of the piston?  It must face forward when the piston is installed on the rod.

The Wiseco expander has this interesting wire running through it.  Never seen one like this before.  I suspect the wire is intended to keep you from overlapping the butts.

Then install a scraper ring in the lower side of the expander, making sure that the butt of the scraper ring and the butt of the expander do not line up.  Try to keep the butts at least 30° apart.  I like to use a method where I sort of spiral the flexible scraper ring down around the piston.  Don’t overdo it, you don’t want to bend or deform the ring.