W-series Connecting Rod Differences
The modified connecting rod has been increased in weight, along with an increase in small end internal bore. It can be identified by a "W" stamped in the side of the rod shaft as shown in illustration. NOTE: A "W" connecting rod requires a "W" piston, new style wrist pin, and modified crankshaft.
Sources Used on This Page: 1988 Nissan 300ZX Factory Service Manual, Nissan Technical Service Bulletin Number TS87-191 Date: December 28, 1987