Need prop advice

[pmilot]

I need some advice on prop.

I have a 2005 TR21X. Last year I was running a 2005 225 HO (E-tec) and was turning a 27" tempest. Had great hole shot and was running 74MPH at 5950RPM.

What I did this year.

I upgraded to a 2010 250 HO.
I upgraded from a 6" set jack plate to a 8" hydraulic.

I tried a 28" raker II thinking that this might be the right prop but hole shot is terrible. I can barely get on plane. To get on plane I have to raise my plate really high to get some air in the pro. But when my boat levels, it blows out unless I'm really careful. Even at that, it's still really hard to get on pad, an this with a light load.

Once I'm on pad the prop feels good. I did not open her up yet (break-in) so I don't have WOT numbers yet, but it has lots of punch once I'm on the pad.

So, is the 28" Raker II too big for my setup ? Anything I can do to it to get the RPMs up on take off ?

Since my 225 was easily turning the 27" tempest, I'm suprised that the 28" raker seams to be too big.

Any advice, really appreciated.

Thanks
Pat

[ELGIN]

The 250HO has a gear ratio of 1.71:1 and the 225HO you were running had a gear ratio of 1.86:1, you will need to drop to a 25 Raker II if you run a fair load in the boat and if you run heavy you may need to drop to a 24.

[DOUGMCGEEFTD]

you might talk to garfish he has the same setup i think.

[pmilot]

OMG

That means with the 28", I am way off. Not even close.

I wish we had dealers who would lend you props to try up here. Looks like I ended up with a 28" that I can't use. And the next one I buy may not be the right one either.

I'm assuming there is no way to add ventilation to this prop ?

Pat

[DOUGMCGEEFTD]

you could send it to mark to add pvs holes or do it yourself as i did on my raker 2's. i drilled the holes to 3/4 inch then i used a 1" bit and countersank about 1/2 way so that i could use the merc plugs in it.

[Garfish]

Oh, yes Mark Croxton can drill the PVS holes so you can customize the amount of escaping gasses. Theory is to get the right combo of ventilation to give the prop enough spin say 4000 to 4500 on launch without blowing out. If you achieve that then see if you can turn it to 5850 or 5900. So I'd say that if you have been able to peddle the 28 up to plane then see if the blade will turn up the max WOT, if it won't then you will have to down size and at that point there is no sense in having the PVS holes drilled. My gut feeling is that a stiff 27p 3- blade is going to be the one. I'd say TXP B&B with a bit of cup and the right amount of vent. I have had such a blade up to 79.1 @ 5850 but in my haste sold the blade without working with it, and it was also in December.

[pmilot]

I haven't tried WOT yet. Still trying to break it in.

Sounds to me I had it all wrong with the 28". I'll try WOT next time out and see if drilling holes is even worth it.

I was wondering how I could keep the boat on plane at 2500rmp. Now that explains it.



Pat

[pmilot]

I was looking at my raker II closely tonight, and I already have ventilation holes on the prop.

They are wide open (no plastic plugs) and are about 3/8 of an inch. There are 3 of them.

So I'm a little confused as to why mine has holes when most say the raker II does not have ventilation holes. I also saw a few pictures of raker II only and none have the holes.

Did Evinrude change there props lately ?

Thanks
Pat

[DOUGMCGEEFTD]

they do have them they do not have pvs holes where you can adjust the size of them. It is easier to fine tune with pvs holes. All these holes are 3/4" hole then a 1" countersink about 1/2 way thru. then go to a merc dealer they are plastic plugs to go in the holes if it vents too much.

[pmilot]

Thanks

I will have a 26" raker II in my hands by the weekend from my fishing partner. Will give it a try and post back. If not I'll have to order a 25" I guess.