Just purchased a 30 Spectre with Mercury 300XS's. I ran 14.5inch 30 pitch labbed cleavers up to around 98 on the limiters. My questions is should I go with the 15 inch or the 14.5 inch 32 pitch cleavers. Any input would be appreciated, thanks.

I'd start with with 15's and you could always modify them to 14.75, which seems to be the hot setup. If you start smaller you cant go back up. Are you looking for 3 blade or 4 blade ??

3 blade, thanks for the reply.

The big cats with O/B's like 15" because of the high engine height.

Congrats, sweet boat. I wanted (still do) one of those for a long time. Enjoy it.

You might want to look at a set of worked 4 blades, they vibrate less, accelerate harder, and carry the boat better. I've got a sweet set of 15x32 4 blades worked by bblades that were my favorite props on my old outboard boat.

Thanks for the input on the props, it's looking like 15 by 32 is the way to start. Hey Stainless what boat did you run your props on? I don't know if I can turn the 4 blades high enough.

I run 32 Bravos on my 30 Liberator cat. Runs 6000 at 97. 30" props are always on the limiter. I also ran 30x15 cleavers and they hit the limiter also. The Bravos are much smoother and get on plane way better. 32x15 cleavers also ran 97. With Bravos, you must get 4 1" vent hole cut into them though. I also had 5/8ths" of the rear of the bell cut off too.
I set up alot of 300xs motors. They run best when propped at 6000-6100 rpm. This is with the 32 Bravos

15X32 3-BLADE Cleavers....pretty much the only prop choice for a 30' Spectre...

15X32 3 blades's are a good starting point but I would would look for a set of 15x32 4 blades. I made the switch over to the 4 blades and the difference in vibration is night and day.