My 303 with twin bravo's has zincs under the cavatation plate just aft of the props that are shaped like an upside-down fin. I have seen other twin bravo rigs with just the flat zincs with no fin.

Should I change these to the flat kind? Am I losing top end this way or do I need them for some reason? It seems to me that the zinc with a fin is mainly for single engine boats to offset steering torque.

Thanks in advance for your comments.

Toolman

flat is fine.

Toolman,
The zincs with the fin are for single drive application and they are adjustable for steering torque. Twin drives w counter rotating props don't need them as they cancel one another out.
They're probably knocking your speed down at least 3 to 4 mph Maybe even 5 mph



Nah , just kidding. If there is any change you'll probably never notice.

PS I have the flat ones on mine
Cal(mopower)

Just take your existing zincs off, hack of the fin with a hacksaw and grind it flush with the surrounding area. Looks great and the material works very easily. No sense buying new ones.