Prop Exhaust vs. Performance Question

[PAkev]

I am considering this Michigan Wheel - Appolo SS prop I found here on I boats:<br /><br />http://iboats.com/mall/propfinder/index.cgi?manufacturer=Yamaha&rotation=Standard&horsepower=150&search=Product&chart=76&pitch=17.00&prop_chart_relation_id=10948&**********=3151756 85&engine_id=421&pf_new=1<br /><br />It boasts contributing to add another 5-10 percent Horsepower due to its unique exhaust porting. Although this feature didn't necessarily hook my attention, the prop seems to be a good value. A few more MPG and/or MPH would indeed be a collateral benefit if the props performance meets the published claims.<br /><br />I just hoped I could get some prop and motor gurus input before ordering it. Helpful thoughts appreciated.<br /><br />The prop will be going on a Yamaha F 150 pushing a 20ft Polar CC Bay Boat.

 

[WillyBWright]

Re: Prop Exhaust vs. Performance Question

It certainly looks like a nice prop. The metal at the hub is thinner than an aluminum. That would allow a larger opening and reduce backpressure on a motor capable of producing enough exhaust to create it. Look at the hub and look at the exhaust pipe on your car. Which motor is bigger? Do you think there's an outboard that's going to have a problem with back pressure with such a large hole? Sterndrives with large motors, sure. An Outboard? Doubtful. Still, I'm sure it's a fine prop.

 

[Dhadley]

Re: Prop Exhaust vs. Performance Question

Looks like a copy of the Yamaha prop. It sure doesn't look like it has much rake. I wouldn't expect it to have much lift if thats what they really look like.

 

[walleyehed]

Re: Prop Exhaust vs. Performance Question

I haven't got my hands on one yet, but they say the trim tab must be changed in several applications, but Rake doesn't "appear" to be an issue. I know of a few runs with one, but I don't know how it was set up, so if I said what their result was it would be biased.

 

[PAkev]

Re: Prop Exhaust vs. Performance Question

When you say it looks like it doesn't have a whole lot of rake does that mean it is "lacking"? <br /><br />Would their 4 blade version linked below afford the lift I would expect from a higly raked prop? Since I boat a few times each season in tidal waters, better hole shot is something I can use.<br /><br />http://www.iboats.com/mall/propfinder/index.cgi?manufacturer=Yamaha&rotation=Standard&horsepower=150&search=Product&chart=76&pitch=16.00&prop_chart_relation_id=11204&**********=473 231516&engine_id=421&pf_new=1<br /><br />Thanks for the replies,<br />Kevin