# Mitzi 17 Prop Advice



## Darkstar (Feb 2, 2017)

I have just acquired a 2007 17' Mitzi skiff and am looking to reprop to decrease porpoising, increase stern lift, and for a better hole shot. No trim tabs.

The hull weighs 530lbs, the engine 220lbs, and approximately 650 lbs of rigging and gear: polling platform, trolling motor, 3 batteries, 10gal of fuel, etc. A substantial amount of weight is at or near the stern with few options to move weight forward.

I load pretty heavy especially with 2 200lb guys and sometimes a third.

Engine: 2007 Yamaha 70 2-stroke mounted at the second hole from the top. May need to come up one hole.

Current prop: Solas Myth 13x19 aluminum

Current Performance: WOT 37 [email protected] rpm fully trimmed and cruise [email protected] rpm.

The boat begins porpoising at 5000 rpm and is fairly severe at wot 5500 rpm.

From what I've read I'm considering going to a stainless 4 blade prop but was looking for some opinions and recommendations from others. Not married to an particular setup. Any advice is appreciated! I posted this over at THT as well.


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## Dawhoo (Oct 27, 2015)

I will check on my Prop but I have same boat and same engine. I get right at 40 and even occasionally 42 with no porpoising. I have mine at the lowest height(top hole) as that is how it came. Mine seems to get better speed then most state, I am beginning to wonder if the lower mounted motor gets this boat better performance.


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## Darkstar (Feb 2, 2017)

That is interesting regarding the motor height. I may give it a try. Do you get a lot of diaganol spray off the transom? Do you have tabs or a fin? I could have probably pushed the WOT and squeezed a few hundred more rpms and a couple of miles per hour but the porpoising was so bad I didn't want to push it. Thanks for your help! I love the boat overall. Took it out for the first time, since the brief sea trial, yesterday and it rode great in a chop, got it super skinny, and it was easy to pole.


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## Dawhoo (Oct 27, 2015)

I have tabs


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## Jomofro (Oct 24, 2016)

I have the same 2007 hull with a 2007 Yamaha F60. I'm running a 3-blade prop but I'm not sure what the pitch is. WOT for me is 4800 rpm's - sometimes up to 5200. I also have trim tabs and I love them. I've never had any porpoising issues and I also usually run with a full load. Darkstar - did you pick this skiff up from the older gentleman in Sarasota? I spoke with him a few times about the boat. Seemed like a very well cared-for skiff but I decided to go with one with an F60 instead of the 2-stroke 70.


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## Darkstar (Feb 2, 2017)

Jomofro said:


> I have the same 2007 hull with a 2007 Yamaha F60. I'm running a 3-blade prop but I'm not sure what the pitch is. WOT for me is 4800 rpm's - sometimes up to 5200. I also have trim tabs and I love them. I've never had any porpoising issues and I also usually run with a full load. Darkstar - did you pick this skiff up from the older gentleman in Sarasota? I spoke with him a few times about the boat. Seemed like a very well cared-for skiff but I decided to go with one with an F60 instead of the 2-stroke 70.


The boat was listed on the Sarasota Craigslist but it was actually in Anna Maria. It was garage kept until about the last year or so; in good condition for a 10 year old boat.


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## Darkstar (Feb 2, 2017)

Dawhoo, if you have a chance to get the info for your prop it would be greatly appreciated!!!


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## Darkstar (Feb 2, 2017)

For anyone with the same setup, I finally pulled the trigger on a Power Tech SCD3 13x17. I decided to stick with a 3 blade prop to maximize efficiency. The boat performs substantially better than with the old Solas. The hole shot is markedly improved and the porpoising is almost completely gone, but is still there at WOT. The new performance numbers are below; loaded exactly like it was previously.

WOT 5900rpm 38.5 mph (trimmed)
Cruise 3700rpm 22 mph (trimmed)

I'll likely try to adjust motor height at some point in the future and will update the info then.


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