650 to 550 top end swap piston question

invalid@example.com (Eric Olp), Eric Olp
Tue, 21 Apr 2026 02:21:32 +0000
Performance/Tuning/Mods

Sorry if this has been covered but I have read most of the information on here regarding the 650 to 550 top end swap and I havent found this question yet.
when doing the swap do I swap both the connecting rods and the pistons or do I just use the 650 pistons on the 550 rods?also do I need a thicker head gasket and if so what are my options. Thanks in advance for any help.