Which prop?
 

Hi guys

I hope you can help me with finding the right props for my rig.

Rig is as follows:

http://dl.dropbox.com/u/2805819/Bill...n565wasper.jpg

I'm currently spinning a P19 VenSura 5700@55 mph, it is 3 1/5" below pad, and ventilates VERY easy when turning and choppy waters.

I'm looking for better mid range and top end speeds, hole shot is of no concern, as I mostly do long cruises.

Can you guys help me get closer to which props fit my rig best?

Thanks

/Martin

Based on what you have said.
You are running really good slip numbers (7%) so the type of prop your running is working . You are very close to limiter for the 225 opti so wouldn't benefit from any more rpm (pretty sure they are on the limiter at 5700-5800rpm?). Don't know much about the prop you are running but other props that are worth a look are trophy and fury (normally have to drop a pitch or 2 with fury as they are really efficient).
What you will benefit from most of all however is a anti cavitation plate. They bolt on to existing cavitation plate and increase the surface area over the prop. Will help with planning and your venting in turns.
Try fast company marine ( www.fastcompanymarine.com )

Hello prepsdk,

I really feel you might be best suited to lower the engine a bolt hole.
Otherwise we do have a number of other propeler options we could send you for testing.
Please let us know if we can help.

Brett

Thanks for your answers :)

Kurt: I really would like to try out different props and motor heights before drilling holes in the plate :rolleyes:
You are correct, my rev. limiter is 5750 rpm.

Brett: I live in Denmark/Europe so sending me props for testing is maybe a bit to difficult, but buying one from you when I have found the best prop is more likely as I buy all my props in USA (they are WAY to expensive here in DK) ;)

I always thought a 4-blade would be best for my rig and thought of a Rev4, but being such heavy a prop I am a bit worried about my LU :)
and Mirage Plus or Enertia P19 / P21 were mentioned to me as possible some of the best choices for my rig, do you agree?

prepsdk,

I like the Rev 4 as well. I like it in a 19 pitch since it will hook up better than a Vensura so the rpm level will decrease slightly. The propeller can be Labbed to decrease the weight substantially.
Can you lower the engine? I'm not a fan of extra cav. plate extensions.

Brett

What's the reason for not liking cav plate extensions? I know the old story that they add load to the existing cav plate etc. But we have fitted them to hundreds of hulls ranging from small tiller steer motors right up to 300xs optimax on race boats. Never seen a broken cav plate and always seen a benefit in one way or another from the addition.
They are so beneficial in fact that they banned them from certain classes in ski racing as it allowed people running them to spin huge diameter props and still pull the load of 2 skiers out of the water. Just want to know if anyone has had problems with them?
Was thinking the rev 4 would be a good choice also.

In rare cases I believe they have their place.
However, in most cases I believe they are a band aid that can be prevented with the proper set up and propeller. Yes they can cause cavitation breakage but more so they can cause drag. Drag is speeds worst enemy. If you set it up as you described below to aid in stopping the venting in turns, it is most definitely scrubbing speed.
For hole shot specific on a 1/4 mile drag boat that has a motor height high enough that when out of the hole the added (Whale tail Cav plate thing) is completely dry, it can be useful. However this is rare too.
Again, the cavitation plate extensions were really invented as a band aid to make a quick fix for poor setup issues or boat manufacturing issues. Or originally as a way to bring the stern of the boat up when it is overloaded, underpowered or over pitched with too big of a propeller when planning. As far as ski racing, ok, there is a very specific instance that few of us will ever deal with. I do understand it there in some conditions. However, I deal with many ski racers from the US as well as Australia and New Zealand and none of them use these.

Anyway, that’s just my opinion. Hey, if it works for you, great!

Brett

All fair enough points made. However sometimes the band aid has the same desired outcome at a far cheaper price!

Brett:

No problem in lowering the engine !

How do you feel about the Mirage Plus and Enertia for my rig?

I think the Enertia or Mirage can each be an option. These propellers should offer higher speeds and better trim reaction compared to your current prop. Your Vensura my be fine if you can get down 1.5 more inches
Let me know the performance numbers if you lower the engine or nay other questions you might have.

Brett