Difference between a large hub prop & a small hub prop?

[ssskdm]

Can anyone tell me what the difference is between a large hub prop & a small hub prop? I currently run a 135 mariner with a 14x19 pitch, 3 bladed SS but want more bow lift so looking at a 4 bladed SS, 13.5x21 pitch prop but that has a small hub.. I'd be greatful for any comments.. k

[TJ]

Don't know about Merc props, but as I understand it, OMC small hub props vent some exhaust gasses to the outside of the prop to aid spinup for better holeshot. The large hub OMC props are all through-hub exhaust. At least thats the difference between my Offshore Renegade and my Bass Renegade. They each require a different thrust washer and I have to put the weed ring on my Ficht when I run the Bass 'Gade or too much exhaust flows over the blades and holeshot slows with a full load.

[KevinA]

If you're looking for more bow lift then look for high(er) rake prop & maybe added cupping. The cup can be re-worked into any SS prop, but the rake is basically fixed. A smaller hub or higher pitch won't do it. For starters I'd try a Stiletto in the same pitch your at now (assuming you're in the top half of you motor's max rpm range). I've had very good luck with these props with regard to lift. Check overtons.com. They let you return props in new condition with a full refund (for 30 days). Another option is contact a custom prop shop & have some work done on your current prop.

[Shellback]

I know on Merc props the Mercruiser I/O prop has a larger hub than the Merc outboard. I can't say if there is a small and large hub for outboards only though.