V4 lower unit on a V6

[Striper80]

My 99 22WA has a 98 Johnson 200 v6 with an SEI lower unit on it. I had to send it back to them because I found some large metal shavings and felt a bit of a vibration. I have a 96 130 v4 that has the v6 style lower on it. On the outside they're identical. I know the gear ratio is different. Anyone know what the difference in propping would be? I'm running a 14-1/2x18 prop. I also have a14-1/2x17 in the garage.