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 40 GTR 
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Post 40 GTR
I have put 5 hrs on my 40 now and I am running a .190 18X54 Stumpjumper. It came with the 3 Blade Prop and I really thought it could push much harder. I ordered a Fat Blade from Gatortail and tried it. I can max out RPM but I only get 23mph in deep water. It gets there fast but that is about it for speed. It pulls away from my Hand really hard though.

I put my 3 blade back on today. Now that I have a good GPS Depthfinder I should get a good accurate speed with the 3 Blade which seems to be pretty neutral.

My first speeds were measured by the builder at 27 to 29 with the 3 Blade so now I can verify that. Planning on taking it out today.

With either Prop I have no problem getting the RPM up. It just does not seem to bite like it should.


Sun Sep 02, 2018 10:03 am
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Post Re: 40 GTR
Send it to baggy


Sun Sep 02, 2018 5:06 pm
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Post Re: 40 GTR
With the 3 Blade I made 26mph yesterday. Guess my boat is just heavy.


Mon Sep 03, 2018 7:52 am
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Post Re: 40 GTR
Seems slow. Buddy of mine has an 18x54 3/16 center console with a 40 PD and he is running 28-29.


Wed Sep 05, 2018 8:03 am
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Post Re: 40 GTR
But this one is extra thick. [WINKING FACE]

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Wed Sep 05, 2018 8:09 am
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Post Re: 40 GTR
What is the transom height and angle?

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Bayou Surface Drive
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Tarkington, TX 77327


Wed Sep 05, 2018 8:23 am
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Post Re: 40 GTR
In your original post you said

It pulls away from my Hand really hard though.

Although we run different motors it sounds like at times you may be trimmed down to much or not enough. Extreme tiller torque is a dead giveaway. Play with your trim up and down and watch your speeds and rps vary. You will find the sweet spot.

And on any given day depending on chop and wind, tiller torque is never static in my opinion.

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Wed Sep 05, 2018 9:08 am
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Post Re: 40 GTR
Dpd is right about that. Also, I find tiller torque to be a lot worse with a 3 blade as opposed to a 2 blade prop, for whatever reason.


Wed Sep 05, 2018 10:31 am
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Post Re: 40 GTR


Wed Sep 05, 2018 12:13 pm
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Post Re: 40 GTR
what is your transom height and angle?

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Bayou Surface Drive
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Tarkington, TX 77327


Wed Sep 05, 2018 2:56 pm
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Post Re: 40 GTR


Wed Sep 05, 2018 3:42 pm
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Post Re: 40 GTR
Put a tape measure on it from the bottom of the transom to the top. If it is 20 and 3/4 -21 inches, it is a tall transom. If it is below that significantly, it's a short transom


Wed Sep 05, 2018 5:51 pm
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Post Re: 40 GTR

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Bayou Surface Drive
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Tarkington, TX 77327


Thu Sep 06, 2018 6:56 am
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Post Re: 40 GTR


Thu Sep 06, 2018 9:44 am
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Post Re: 40 GTR
Which means you might benefit from adjusting motor mounting. Up an inch, left or right a half inch, etc to improve performance and eliminate tiller torque.

Also sounds like your builder jipped you out of almost 2 inches of transom height lol

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Thu Sep 06, 2018 9:56 am
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Post Re: 40 GTR
Yep, and that extra 2 inches makes a big difference (what she said) :D


Thu Sep 06, 2018 10:13 am
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Post Re: 40 GTR

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Thu Sep 06, 2018 1:06 pm
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Post Re: 40 GTR


Thu Sep 06, 2018 1:58 pm
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Post Re: 40 GTR
GTR's usually do the best 15-20* 20* giver more reach in mud. I find with a 15* like traditional outboard transom the GTR can trim up higher... But the height cannot be too tall.
It sounds a lot of your issues are from hull setup. Not pointing fingers but not many guys have run hulls with certain setups to see whats the optimum transom height/ angle.

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Mon Sep 10, 2018 5:11 am
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Post Re: 40 GTR
Adjusted the trim tab just a little and paid attention to leveling the load. Got 28 in deep water this weekend. After getting on plane I ran about 3600 or 3800 and cruised at around 24 to 26. Motor is new so I was not to eager to run wide open too much right now. Tiller torque was almost perfect.

Just wondering how many of you run at max rpm which for me is about 4200 all the time.


Tue Sep 11, 2018 6:56 am
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Post Re: 40 GTR
Wot 4250 ish wont hurt a thing. Its got a 3 year warranty let it eat.

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Tue Sep 11, 2018 6:58 am
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Post Re: 40 GTR
I run anywhere from 4250 to 4500. Sweet spot for me is 4450 with both my worked props


Tue Sep 11, 2018 11:05 am
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