OEM prop or upgrade

[E-vader]

I have a 16' Invader with a Volvo AQ131D / 275A drive. Current prop is 14x19 rh and pretty nicked up. There's a 15x19 SS on ebay that fits at a fair price. What impact does increased diameter have on the boat's performace? There appears to be plenty of room for the 15" diameter prop on the current drive. If this doesn't sound good , what's a good recommendation?? The boat is about 1800lbs, the drive ratio is 2.15:1 and the listed throttle range is 4700-5000 rpm. I had the boat out over labor day and top rpm was about 4750. We mostly ski/wake or tube and I'd like to get the best performance outta this small engine without overworking it too much.

 

[Dhadley]

Re: OEM prop or upgrade

It's not so much the extra or less area on each blade but what the manufacturer did with that area or the lack of that area. Unless you are comparing props from the same manufacturer and same style it's impossible to tell without testing.

We can't think about the advantages of changing the X dimension on an I/O like we can on an outboard, it's way to difficult and expensive. I've had 13 3/4" props out perform a 14 1/4" prop and a 14 3/4" prop was better yet.

I'd say that if you can get the prop at a price that you're comfortable with for a spare prop then get it and test. If you figure you're buying a spare and it works out as a main prop, you win!