# Shadowcast 18 - new prop and cav plate



## Icroc (Feb 23, 2013)

I just got a new Tohotsu 30 on my Shadowcast 18. I am coming from a 2 stroke Evenrude 25. 
This motor is significantly heavier than my 25. So I'm expieriencing a good bit of stern squat and slow getting on plane. My batteries and fuel tank are at the bow. I'm currently running a 3 blade aluminum prop 9X13(running aluminum because of the # of rocks where I fish). I am also getting a lot of cavitation in my turns. 

To help solve my issues I have ordered a 4 blade aluminum 9X12 and a Shaw Wing. I opted to not put trim tabs for the sake of weight and drilling additional holes in my hull. 

Does anyone have any experience with this? Any comments or recommendations are welcome.

Thanks in advance!


----------



## Smackdaddy53 (Dec 31, 2012)

Trim tabs would help counteract the squat on holeshot. I don’t know how some people run boats without tabs, they are something every hull needs in my opinion.


----------



## Icroc (Feb 23, 2013)

Thanks for the suggestion. I really appreciate it.


----------



## Guest (Dec 21, 2018)

In my opinion any gain by going to a 4 blade is lost in the aluminum. With that tunnel you should be able to get the motor up high enough that a stainless wheel never or rarely sees bottom provided she is set up properly. Tabs are a Godsend on a skiff! My best advise is this... give the folks at Ankona a call! They know their product better than anyone and are very helpful from every post I’ve ever read about them here and elsewhere! They can probably tell you what needs done in a few short minutes, James


----------



## Israel luis (Nov 25, 2015)

Put a stainless steel SRA4 blade, I have a 16 Ankona Shadowcast with a 30hp Evinrude Etec and I had a 3 blade before sra 3 and due to the tunnel I was ventilating a lot but my top end was awesome. When I switched to the stainless 4 blade I could basically go on plane at half throttle and the boat is much more stable and turns much nicer is the 4 blade. 

And to be honest you should be running more HP, my buddy has an Ankona Shadowcast 16 as well as I do and he’s running a 1997 2 stroke 40hp . Shadowcast are well built, and limiting them to the motor specs isn’t enough. When I purchased my shadowcast it had a 20 hp and honestly that thing was so slow I wanted to cry. Believe me I know no one in the forums that runs a 20 hp Shadowcast 16 does not get any near the high 20s because the tunnel slow you down a lot


----------



## Icroc (Feb 23, 2013)

I installed the Shaw wing and finally got my motor mounted high enough that it is not spraying everywhere. The cavitation plate is about 2" above the top of the tunnel. I was not able to find an aluminum 4 blade prop, so I ordered a 3 blade stainless with cup from Jack Forman. This should help with the cavitation in turns and in chop when trimmed up. I also have a wedge between my stern and motor to give some negative trim. Both have worked great so far. The negative trim and Shaw wing has given my stern lift when running slow n shallow water. It also has helped my boat get on plane quicker. I'm getting 25 mph wot and trimmed as high as I can without cavitation.


----------



## Icroc (Feb 23, 2013)

I tried the Jack Forman prop this weekend. It did the trick. It's like a different boat. This prop has made a huge difference in the turns. I can also trim up a lot higher than I had been without cavitation. I also lost no speed. I'm getting 25 mph WOT.


----------



## Feltonard (Nov 6, 2019)

Icroc said:


> I tried the Jack Forman prop this weekend. It did the trick. It's like a different boat. This prop has made a huge difference in the turns. I can also trim up a lot higher than I had been without cavitation. I also lost no speed. I'm getting 25 mph WOT.


I know this thread is old, but what prop and pitch are you running exactly? I have the exact same boat and I’m trying to figure it out


----------



## Icroc (Feb 23, 2013)

I can’t remember what prop I had. I sold this boat last year and got a Waterman 18. Give Jack a call. He can help you with what pitch to get for that boat. Jack knows his stuff!


----------

