Prop to pad ?

[Rocco73]

Typically speaking if you increase your prop size dose the prop to pad need to move up or down? I have a 2001 tr-21 with a 2001 225 Yamaha efi vmax ox66 3.1L. Since I’ve had the baot I’ve run a Yamaha 23-M at 2 1/2 below pad. Oh and I’m at 5200 feet. I dinged my prop up so I’m experimenting with other props and was wandering if the ptp needs to move wile doing this? Thanks

[J Risco]

TYPICALLY, the bigger the diameter the higher likes to run. BUT every prop/boat/motor combo is different, so you have to try them at different heights to see what it likes.

[Rocco73]

I tried a 25p 3 blade tempest and could only hit 50 at 5000 rpms. It felt like I wasn’t getting enough bow lift from it. The boat was just running flat and no mater how much trim I put on stayed flat. It could just be to much prop. But I thought maybe moving th motor around might help.

[Fatshaft Merc]

No lift, go down on the plate.

[J Risco]

Yep, if the prop cant grip/get traction and you arent getting any lift you need to go down. Might be that it needs some attention from a good prop guy.

[mdtritn21]

How many rpm's did you turn the 23 M and how many many MPH compared to the 25 Tempest at 5000 rpm's at 50 mph. Your at 5200' and a 25" prop is too much pitch for a 225 at that altitude even if it has 1.81 gears.

[Rocco73]

How many rpm's did you turn the 23 M and how many many MPH compared to the 25 Tempest at 5000 rpm's at 50 mph. Your at 5200' and a 25" prop is too much pitch for a 225 at that altitude even if it has 1.81 gears.

I turn the 23-M wot at 5800 64 65 mph gps. The Yamaha specs say 5800 is max rpms, I’ve been told no this site that it’s 6000 but have never hit that even at 3200 feet. At 3200 feet I hit the same speed and rpms. I’ve also tried a 23p tempest plus with no change in rpms or speed. The only difference between the M and the tempest was the boat felt a lot more lose the the tempest.

with the 23 M I’m around 50mph at 5000rpms but the bow comes up and I then gain speed and rpms.

[mdtritn21]

There are a few guys on here who run at 3600 ft (Lake Powell) and they run up to 23" but not more and some run 21" props over that elevation. Your doing pretty good at 65 mph.