Z18 175hp new 4 stroke

[Nova Kaw 650]

The Mercury site shows the 175 Pro XS as a V-6, not a V-8.

You are correct; it is the V-6.
A 3.4L 4-stroke will have a hard time running as strong as a 2.5L 2-stroke.

[potomacbassin]

It's actually not expensive. The 175 to 250 ProXS are identical motors. The 175 is limited to 175 by computer programming; I'm don't know if the cams are the same, but even if the cams were different, there's no increase in cost.

I doubt the cost to the manufacturer doesn’t increase with two options rather than one. Economies of scale.

[AuMiner200]

The engineering is done.
175hp is 175hp, 250hp is 250hp. Doesn't matter if it's 2-stroke or 4-stroke.
Horsepower rating for outboards are a joke anyway. The marine industry should be honest and rate motors by displacement, like every other motor based sport.
The difference is the displacement vs. weight. Add another liter to the displacement of all the 4-strokes, make it light, call it a 250hp (wink, wink, nod, nod) and people will be saying "what's a 2-stroke"?
There's a reason why 250 2-strokes run in the 450 4-stroke motocross class. It takes that much extra displacement to run with a 2-stroke. You have to add displacement to a 4-stroke to get it to run with a 2-stroke of the same rating.
People want a motor that will run lean for more than 15 seconds w/o melting a piston, hence the move to 4-strokes.

I have to agree regarding the 2vs4. My 2 stroke yz1255 Motocross bike will run even with my buddies yz250 F 4 stroke - and his is fuel injected ... just sayin