90mm piston ring compressor

Scaled, extended, and strengthened to handle compressing the rings on a 90mm piston, such as for Saab 9-3 engines.

I use vise grips to squeeze the two tabs together, then tap the outer skin of the ring compressor with a rubber mallet to close/equalize any gaps seen between the piston and the compressor. For me, the gap closed effectively all the way, allowing plenty of clearance to tap the piston down into the cylinder.