38 prop size

dwigle

Member III
I need to replace my current 15X11 2 blade prop and was wondering what others were using. The P.O. repowered with an M35b and am trying to make a decision on a new prop, especially for powering up the California coast. My current concern isn't so much about drag, but beating into the current and wind coming back from Southern CA. While folding/feathering props aren't out of the picture, fixed is more within my budget.
Anyway, I'd like input on what has worked for others, and recommendations on types of props.

Thanks,
Don
 

rwthomas1

Sustaining Partner
Hello Don,
I have a 16x11 two blade and it is fine on flat water but sucks like yours into wind, tide or seas. I have purchased a new Variprofile 3 blade feathering prop to go on for this season. If you can wait 5-6weeks I'll let you know what I think of it. Variprofile can be found here: http://www.varipropusa.com/ Not cheap but can be removed whole from the shaft easily, pitch is adjustable easily, forward and reverse can be different pitch if needed. As you can guess it isn't cheap. I got really tired of crappy motoring performance and figure the reduction in drag sailing should be good to. I almost got a Campbell sailer but what the he!! its only money..... RT
 

u079721

Contributing Partner
IIRC the specified prop for a E38-200 was a 16 x 13 two blade. If so, then small wonder that your 15 x 11 two blade is a bit weak.

In our case the PO had replaced the stock prop with a three blade 16" diameter Max prop set to 13" pitch, which was way too much. We finally settled on 16 x 9.8 as a pretty good setting for the Max.
 

vbenn

Member III
38 Prop

My '97 E-380 came with a bronze 15x10 3-blade prop which was more than adequate to push the boat into weather, but caused excessive prop walk in reverse and cost >1 knots/hr under sail. I switch to a Variprop feathering prop DF-107 16x11 2 yrs ago and have been very impressed. It's expensive but worth looking at if you want a robust feathering prop. I also looked at MaxProp and AutoProp.

Vince Benn
Wild Blue
E-380 #22
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
My '97 E-380 came with a bronze 15x10 3-blade prop which was more than adequate to push the boat into weather, but caused excessive prop walk in reverse and cost >1 knots/hr under sail. I switch to a Variprop feathering prop DF-107 16x11 2 yrs ago and have been very impressed. It's expensive but worth looking at if you want a robust feathering prop. I also looked at MaxProp and AutoProp.

Vince Benn
Wild Blue
E-380 #22

Hi Vince, Just a question from the cheap seats, if I may...
Was there anything in particular that came out of your research that made the "Variprop" a better choice than the "Variprofile" model. Is your prop a three or a four-blade?
Thanks,
Loren
 

rwthomas1

Sustaining Partner
Loren,
My two cents on the Variprofile vs the Variprop; In all my shopping looking at every option out there the Variprofile is the latest and greatest from Variprop. It has a very small center hub, at least 1/3 smaller than anything else. Supposedly has special stainless gears in it. Blade design is something called the "GAWN" profile, supposed to be just as efficient as a regular prop blade even though it looks flat. Vari has a bunch of computer test data to prove how low drag it is, even at an angle like on a shaft. No assembly required, comes pre-pitched, simple to install and adjust if it needs it. No mods to the shaft either. The machining is top shelf, I used to work in a high end machine shop and it really is artwork. I just hope it lives up to the hype. RT
 

vbenn

Member III
My VariProp is 3-bladed. The VariProfile was introduced 1 yr after I purchased my Variprop. I called the US distributer about the difference between them and he told me that the blade area of the VariProfile was smaller, hence not as much thrust. The Variprop is their top-of-the-line prop.

Vince
 

rwthomas1

Sustaining Partner
Heres a shot of the old 16" two blade with the new Variprofile. Big increase in blade area yet still a fairly small center hub. Should work as expected.

RT
 

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Dan Morehouse

Member III
Don,
I just installed a new Kiwi Prop on my 38. $1300 for the prop. So far I've gotten to motor it about 50 miles from Napa Valley Marina down to Brisbane by SFO. Except for an initially harder punch, forward thrust seems about the same as the original two blade, so I am going to adjust the pitch. Reverse pitch is not adjustable, but I was startled by how this thing jumps out of a hole in reverse. Gains sternway almost immediately, and the propwalk doesn't get a chance to assert itself before the rudder bites. And the blades don't just feather, they vane individually with the water flow past them. Pretty happy so far, but the jury is still out on whether increasing forward pitch will improve performance. My engine never gets above 160 degrees at cruising RPM, so I think I have some room to pitch higher.

Dan Morehouse
1981 E-38 "Next Exit"
 
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