# Repropping Ankona Shadowcast 16 w/ 2014 Tohatsu 20hp 4s (Elec. St./ P.T.T)



## SaltyNShallow (Jun 1, 2018)

I'm looking into re-propping my skiff by replacing the stock aluminum with a SS prop. I have never ran a stainless prop on an outboard with anything less than 50hp and am not sure if I will see better performance when switching over. See boat info below:

2014 Ankona Shadowcast 16 (with tunnel)
2014 Tohatsu 20HP 4S electric trim/ tilt (15" short shaft/ tiller)
Stock Aluminum Prop (9.25 x 10P)

Hull weight w/ engine - roughly 500 lbs (with full tank of gas & gear)

Normally fishes out of it 2 people (myself and friend) on the skiff. I weigh 220 lbs and fishing buddies are between 180-230 lbs. I fish alone only <50% of the time.

RPM @ WOT w/ 2 people + gear (appx. 5850 rpm according to tiny tach)
Max speed @ WOT w/ 2 people + gear: 20mph (+/- 1mph)

Splash line is currently at half-length of boat, maybe 1-1.5ft back towards stern, at most.

I am satisfied with performance with the stock prop but i feel like theres a little more left on the table and could be better. Looking to get a bit more speed if possible, while maintaing good holeshot and bite... in other words, an "all-around performance prop" that is better than stock and is more durable than aluminum. I know its either holeshot or speed and not both but i'd like to be "in the middle." 

Currently looking at the Powertech SRT3, just not sure what pitch. I am open to any suggestions, even 4 blade (a few people said i can even get better speed and performance with a 4 blade?) Any insight can help. Ive read previous threads regarding the subject and still dont feel like I can see much improvement over aluminum besides durability. Ive done the obvious things for keeping weight off the boat like limiting gear, leaving the chunky friends behind (sorry dudes, tippy boat... cant be tippy AND slow), and shifting weight around. Sorry for the long winded explanation but just wanted to supply as much info as possible. Thanks in advance for any help!

Regards,

Chris


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## ZaneD (Feb 28, 2017)

I also have a SC16, mine has a tiller Yamaha F20. I recently switched props for much the same reason you are describing, see below for my results (light load, 1-2 people, probably 500# worth of gear and passengers):

20-22 MPH with stock AL 3-Blade 9.25"x10P
23-25 MPH with new Solas Saturn Stainless 3-blade 9.25"x11P

I bought the Solas prop from iBoats.com for about $140 which I thought was a good deal, and I've been very happy with the switch. In addition to the slight speed increase the stainless prop hooks up better and performs better in turns. I don't have a tach so no details on that from me, but I will say that it is running lower RPM based on feel/sound.

Generally going with stainless is preferred for durability, speed, and decreased prop slip (= speed). In your situation (and mine) I would avoid the 4-blade because although it will increase holeshot and slow speed handling, it will likely lower your top end.

Most likely the 9.25"x11P will be best for you, you'll probably lose a few RPM's but pick up the difference in speed because of the pitch increase. Good luck and post your results so we can compare!


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## bobber (Sep 29, 2015)

I also have a 2014 Hatsu 20 tiller,no electric, on a 15 Johnsen , probably a bit heavier than your rig. After trying several different props I ended up with the PT SRT 9.5 x 9. 2 people,full load WOT is 5800 @ 20mph, can hit 22mph solo. Probably could gain a bit of speed by having the pitch changed to 9.5 but it's not worth the money, I'm good with the current performance and especially the hole shot and lower speed planing ability. Keep in mind the SRT is a 9.5 diameter and a large blade surface which does matter at this low hp level. If you decide on one,start with the 9.5 x 10, your boats lighter than mine which has a stainless pipe platform on the stern and a troller with battery on the bow.
As a wise man once said,if you wanna get there earlier,leave earlier.


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## SaltyNShallow (Jun 1, 2018)

Sorry for not answering back sooner. Didnt realize it had been this long size i posted on the forum.

Thanks for the replies! Based on a few prop techs I have been able to speak to they made the same recommendations. They did mention that at this HP level it is a game of inches. Like everything else in this life, where there is a benefit, there is compromise. I might gain a couple MPH but at what cost? Loss in holeshot? Compromise handling? Increased engine wear due to increased load?

Considering what i know now, I think i will go with the common recommendation which is to stick with the same pitch. Starting with the PowerTech SRT3 9.5 x 10P as a base line and go from there. Depending on the performance, I can then further fine tune what best works for me by trying different pitches at the cost of sending it back + restocking fee.


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## bobber (Sep 29, 2015)

Any results?


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## SaltyNShallow (Jun 1, 2018)

I finally was able to pickup a new PowerTech SRT3 10p a couple weeks back and was able to take out the skiff this past weekend. Overall, im impressed and pretty satisfied with the results. Loaded down with gear, cooler full of ice food and drink and the wife and I, i managed to top out at 22.5-23mph WOT. RPM's dropped to 5560 WOT but that was expected considering its turning a larger diameter/ heavier prop. Holeshot improved some aswell. Cant wait to take out the skiff soon on a bare bones solo trip with just a fly rod, some flies and a small cooler and see how she handles and what numbers she puts down.


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## Fred land (Feb 22, 2019)

Good info, thanks. Trying to go stainless as well on my 2018 Tohatsu 20 on a Santee with jack plate. Was thinking the PT or Solas Saturn 11P. Running a 9.25 x 11.5 AL now.


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## SaltyNShallow (Jun 1, 2018)

I was looking at the Solas because of it 9.25 diameter but my curiousity got the better of me. I was curious to see what numbers and performance id get with a bit larger diameter. I have always heard of positive reviews from Powertech so that's the reason i went that route. So far, im liking it!

If you do decide on the Solas, please post your results. Curious to see how it performs for you.


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## Fred land (Feb 22, 2019)

Will do. I run a 4 blade PT on my other boat (CC) sometimes with good results with a heavy load. You feel the 20 Tohatsu handles the extra mass of a stainless with no problem?


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## SaltyNShallow (Jun 1, 2018)

In my opinion, it handles it just fine. At no point did i feel like the engine bogged or struggled; even from a standstill getting up on plane. As mentioned previously, only thing i noticed was a slight drop in WOT RPM's but still safe within the engines RPM limit range (5400-6100 if i remember correctly)


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## RG Air (Nov 10, 2015)

i have a 2016 skimmer and tohatsu 20hp power tilt. The stock aluminum prop needed to be replaced but prior to that i added a permatrim. When cruising through no wake zone she rode bow high... for that alone i wanted it... Secondly i hoped that it helped with drifting in turns which it really did. There was no issue with getting on plane but it certainly made that even shorter. The aluminum stock prop had a bit of a bend in one blade but never really seemed to be an issue. I replaced it with the Solas stainless 9.25 x 10 and it seemed to be slightly better. Im not sure about RPM but if i had to guess I'm at the top of where it needs to be maybe close to rev limit at WOT. On phone GPS speed app I'm seeing it bounce off of 28mph. Motor cav plate is pretty much even with hull and i usually give one touch up on the trim


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## SaltyNShallow (Jun 1, 2018)

Went on a solo trip today and recorded new figures. WOT RPM at 5857, Top Speed 25.4 mph.


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