ounces add up to pounds.
you do enough of the little stuff and reap bigger rewards. say running the smaller smaller journal lets you run a smaller bearing, that heats less, which means you can run it harder, longer or at a higher rpm without failure and it has less parasitic loss. it might be worth .25 HP from idle to 4K but if it's worth 5 from 5200~7000 and it keeps the engine in one piece long enough to finish the race then that's a worth while upgrade.
