Impulse 31 setup

[sigma962]

Need some assistance w getting my new Impluse 31 up on the "pad" and keeping it there.

I know you can adjust the trim tabs, battery placement, prop strut angle...etc. Ive tried lots of combinations w no solid results.

The boat is all stock...running 2 venom 2s 30c 5000mah in series. Man made pond that I run on is smooth as glass, no chop.

Please give me some advice as to eliminate the porpoise effect...at least a trouble shooting guide.

Thanks.

[Make-a-Wake]

I found that i actually had to give the strut/stinger some POSITVE to calm the propoising

[sigma962]

Noob here in boats...that means moving the strut up as to make the prop closer to the surface?

Thanks.

[Make-a-Wake]

Yep

[stadiumyamaha]

on my impulse all it took was a small adjustment downward on the trim tabs. Before, it was really bouncing badly.

[stadiumyamaha]

also make sure the tabs are above the bottom of the boat about an 1/8"

[Back-lash]

I'm having the same issue with my boat. When you say small adjustment, do you mean just bend the tabs down a little bit? Or do you slide the tabs lower. Currently I have the tabs about 1/8 above the bottom. I was thinking of sliding them down a bit, but it sounds like that's the wrong thing to do.

[stadiumyamaha]

Don't slide the tabs, leave them at about 1/8" and bend the tabs down. It doesn't take much so start with very small adjustments. I use some long flat blade vise grips so it makes contact with the entire surface of the tabs. You dont wand to bend them so that they are curved. You want to adjust the angle of the tab length in relation to transom.

[Back-lash]

I added a little positive angle to the strut, and bent down the tabs, and the boat ran great. No porpoising at all. Thank you!

[Make-a-Wake]

Sweeeeeeeeet!!!

[stadiumyamaha]

Great.

[stadiumyamaha]

You may find if you keep the strut neutral and adjust the tabs further it should run faster. Just a thought.

[Back-lash]

Sounds good. I'll give that a try. I've been around offshore boats all my life, we usually try to use as little trim tabs as possible. We adjust attitude with engine trim (same as adjusting strut angle). We only use the tabs to level out any list depending on gear and fuel. I guess in RC boats it's different. I'll give that a try once I solve my heat issues. I upgraded props, and now I have to change all my connectors, the Deans I was using melted. Thanks for the help.

[Make-a-Wake]

Why mess with it if it "ran great" .......?

[Back-lash]

I hear you. I tend to follow that rule. Once I fix my other issues, I'll always try to tweak things to get the best performance I can. Now, the reality is that I really don't have a way to accurately measure speed at the moment, but when I do, then I'll start trying different things. That's the problem with this hobby, it's addicting, and you always want more speed.

[Make-a-Wake]

I know how that goes, but i messed with a great running boat once to get that extra 1-2mph out of it...............for what i'll never know..............and i took me 2 months to get it back running right........

[Back-lash]

Good advice. I'll definitely keep that in mind.

[Darin Jordan]

I know how that goes, but i messed with a great running boat once to get that extra 1-2mph out of it...............for what i'll never know..............and i took me 2 months to get it back running right........

ME TOO!

Guys... If you really want to give yourselves a thrill, setup a course and work on DRIVING better, rather than going "faster"... It's amazing how slow a "50mph" boat looks when you get it out there with a couple of 40-something MPH boats being driven well! It's a heck of a lot more fun to try to drive precisely, than it is to just zip back and forth in front of the dock...

Unless, of course, you are running a SAW Time-Trial event... :D

[stadiumyamaha]

+1 on that Darin.
My buddies and I have been chasing speed for the last couple of year and just recently started setting up a course to run five lap races. It's much more fun and the boats that have the highest top speed are normally the slowest in a race type situation. My impulse kicks but on 4s2p running a cc1515 2200kv even though the 6s boats are much faster in a straight line. The only problem I do have is that the impulse will stuff every once in a while in rough water.
What I was trying to get at with the trim tab/strut adjustment comment is that you don't want them fighting eachother and to find a good balance between the two.

[stadiumyamaha]

Great job on the hull too. It's tough as nails. I've stuffed mine several times, ran it up on shore and have had a catastrophic esc failure that blew the taped lid three feet in the air and the hull(once replaced with new equipment and de chard) has no more than a few gel cracks. Kuddos

[Darin Jordan]

Great job on the hull too. It's tough as nails. I've stuffed mine several times, ran it up on shore and have had a catastrophic esc failure that blew the taped lid three feet in the air and the hull(once replaced with new equipment and de chard) has no more than a few gel cracks. Kuddos

That's good to hear. That is actually just white paint over white primer on the hull... I've had mine start to get "hairlines" in the deck along the seam from hard flips... which cause the deck to compress and stress the seams... I solved that from happening by using 2-part expanding foam inside the front along the seams, and also a little bit on top of the factory flotation to support the deck... solid as a rock now...

The boat isn't perfect, but it's darn good, as far as I'm concerned. It's definitely a versatile and solid package that can be developed any number of directions successfully.

[stadiumyamaha]

I put carbon fiber on the lid after crushing it on a bad flip and it's solid now.
I will probably do the front now that you mention it. Every time I stuff it I expect it to come back up with the nose split but it hasn't happened yet.
Thanks for the tip.

[Skullcracken]

Now pull off the boring decals and swag it up...2012-02-04_09-32-55_783.jpg2012-02-04_09-33-20_2.jpg

[Skullcracken]

BTW, not you stadiumyamaha, those vinyls on the side are sweet

[stadiumyamaha]

Thanks. Those are some old villain decals that I hacked up to fit. The pin striping is just some cheap car stuff.

[Filmgaffer]

Thanks for the tip on the trim tabs.

[J.W. Pepper]

I recently got a IM-31(V1), purchased a set of these to make trim tab adjustment far easier... http://www.offshoreelectrics.com/pro...d=ros-spdt-150

They're a bolt on replacement for the stocker's, well worth the money.

[Filmgaffer]

I was looking at these wasn't sure the size and had'nt even put it in the water till today. Might look in to but I'm worried about the added weight at the back.
My new favorite boat is this IM31v2. Stiletto still fun too.
Now that its glued in.

[J.W. Pepper]

I was looking at these wasn't sure the size and had'nt even put it in the water till today. Might look in to but I'm worried about the added weight at the back.
My new favorite boat is this IM31v2. Stiletto still fun too.
Now that its glued in.

I have a set, the tabs are the exact same size as the stockers, those adjusters are very lightweight (couple ozs), made from CNC'ed aluminum billet, work with the V2 boats too. I haven't put mine on yet, but from what I can see, the stockers are attached with self threading bolts, if true, forget about most of those bolts in the pix, 2 bolts w/2 lightweight nuts for adjusting.

They're made by SpeedMaster - I Googled them multiple times and can't find the home page, but this what the kit looks like... http://www.rocketcityracing.com/Spee...50_p_1299.html - I got a crap load of hits the last time I looked them up.

Everybody but Steve sells them in 4-paks, gee that's nice, what do I do with the other set?? I bought Steve's, also got his upgrade flexshaft & Octura coupler - bit under $60 delivered, worth every penny.

[Mcpot]

Hi everyone I'm new to the forum and just grabbed an impulse 31 v2 and was wondering what prop I should go with ( 3 blade or 2)or just leave it stock