75+MPH Traxxas Spartan

[justafatman]

Hello everyone, new to boats and I'm looking for some advice.

I have a spartan with the SeaKing 180 v3, pushing a 2200kv x2 leopard on 6s. x640 prop.
I only use High mAH packs (currently 7400mah SMC and 8000mah Flurion)

Im able to hit 75 or so when the water is very smooth
but the second lap around the pond I cannot open it up without getting extremely risky
How do I go about keeping this thing planted?


My other issue tI am having is a "small" temp issue.
ESC, Motor, Bats are all reasonable (140f, 110f, 120f respectively)
The Cap pack before the esc is the issue. I have seen upwards of 240f!!!

Mind you that IS after 20ish minutes of running as hard as i can push it....
Is there a way to keep those poor things cool?

[Bp9145]

With a 2200kv motor you're setup is good for 4S and risky on 6S but for saw runs ok. . .prop down if you continue to run on 6s otherwise run on 4S and try the prop you have now and if the temps are cool then prop up. But if you continue on 6s don't run WOT all the time. .Also, if you don't have dual cooling, one for motor and one for esc, I suggest you add another cooling line but right now you have a hot setup and your electronics will not like it and eventually in the long run they will say nite nite and quit on you.. . .heat is not a friend to motor and esc

[fweasel]

That hull definitely prefers some weight up front, but with the battery's you're running, I don't think that's your problem. The fact is, 75mph is just more speed than that hull is designed to handle. The Spartan is known to exhibit chine walking (wobbling from side to side) at speed and its the result of the strut being positioned too close to the keel of the hull. When it starts, you can let off the throttle a little to settle it down or give some rudder input. I've found it happens less frequently if you ramp the throttle up smoothly vs. mashing it down. The real solution is to raise the entire drive line higher on the transom, but that's not a project most "beginners" are going to want to tackle as it involves drilling new holes and filling the old ones.

[Checkmateguy01]

The upgrade trim tabs and turn fins really helped the handling and stability on my Spartan, but i also only run mine on 4S just as a fun toy at the family cottage. At 75mph, i'd be looking at a better hull meant to handle that kinda speed, if there really is one. Nothing against the Spartan, like i said i have a first generation Spartan (with the sloped nose) and i like it, i've put the newer Castle motor in (that they come with now) and switched to a Hobbywing 180 esc, very reliable on 4S. Anyway, if you are gonna run it that hard, definitely upgrade the transom hardware!

[Doby]

Shorten your run times!

[R2315]

Hello everyone, new to boats and I'm looking for some advice.

Welcome to OSE!

I have a spartan with the SeaKing 180 v3, pushing a 2200kv x2 leopard on 6s. x640 prop.
I only use High mAH packs (currently 7400mah SMC and 8000mah Flurion)

Run it on 4s or swap the motor to a lower kv, 1500kv being the most. You can always try other props and gain some extra speed while keeping things cool.

Im able to hit 75 or so when the water is very smooth
but the second lap around the pond I cannot open it up without getting extremely risky
How do I go about keeping this thing planted?

75+mph with a plastic hull may lead to trouble, its just not designed to go that fast.

My other issue tI am having is a "small" temp issue.
ESC, Motor, Bats are all reasonable (140f, 110f, 120f respectively)
The Cap pack before the esc is the issue. I have seen upwards of 240f!!!

Your temp issues most likely have to do with your setup being in saw Territory although a small prop, being new to this, try and get your rpm around 30,000rpm.
kv_voltage[1].pdf

Mind you that IS after 20ish minutes of running as hard as i can push it....
Is there a way to keep those poor things cool?

This is where I'm confused because 8000mah over 20min = 24amps which seams quite low for 40,000+ rpm. do you have a low voltage cut off set and how many mah are left in your packs when you bring them in to re charge?

Here is the link to the OSE calculator https://www.offshoreelectrics.com/conversion.php and if you do enough reading you will no doubt get things under control. Good luck!

[justafatman]

@Bp9145 yes I have twin picks and 2 full separate paths for the water down to the twin outlets.
Never thought about trying 4s, according to calculator from @R2315 that would cut me speed from 70ish to 50ish on nominal voltage.

@fweasel So THAT'S what that is called, I have figured out rolling into it and not going strait but with a very slight turn it helps tremendously
That's also one of the reason I wanted the bigger batteries, Hold up to the abuse of boats and keep that nose down! haha
So the effect your looking for from moving driveline up would be to put the hull back into the water?

@Checkmateguy01 for those upgrade, would i be looking for bigger or longer or adding another set of?
All i have really seen is the hot racing stuff, doesn't really seem like much of an upgrade because its the same size ish
I know there is bigger hardware here but don't know what would be good for my speed-hull
Yeah the plastic hull is not gonna live through a bad crash,
I have watch my buddys spartan basically explode after a triple backflip and nose first touchdown on the water at speed... lol
Pro-Boat Voracity is what i am looking to do next. seems like a stronger hull and I have seen pro-boats do great things!

@Doby I try to only run with friends and not run when they are not in the water too. I cant help myself though... lol

@R2315 Thanks for the greeting! lol I might have to try 4s with one of my more aggressive props i got from a friend for dirt cheap,
kinda figured higher voltage higher rpm less prop would equate to better temps like volt up gear down sorta ya know?
yeah I know the hull wont last when I crash big, but that's part of the fun I guess, anytime you grip the full throttle even for a second you start to get some adrenaline shakes
not you boat but you hahaha
it is just a guess but that still dose seem like a low amp for how hard its running, I HAVE to be wrong in my time estimate....
LVC is on but set to 3.4v so the boat stops at around 3.6 Haven't ran twice in a row yet so its always been from lvc to storage, then to full charged the next time though
Thanks for the calculator, I have enjoyed trying a few things on it

@everyone Thank you all for your input, Would anyone happen to know of a like 14aH 2s I could use? need the weight lol

[fweasel]

So the effect your looking for from moving driveline up would be to put the hull back into the water?

Exactly

[srislash]

I’ll throw this out there in regards to capacitor heat, how long are the wires going to them? How many connectors and what size? And what ‘C’ rating are the packs?

But also the caps will build heat and don’t really have any way of cooling themselves so long runtimes will hurt them. Especially if any of my above questions are a problem.

[justafatman]

I’ll throw this out there in regards to capacitor heat, how long are the wires going to them? How many connectors and what size? And what ‘C’ rating are the packs?

But also the caps will build heat and don’t really have any way of cooling themselves so long runtimes will hurt them. Especially if any of my above questions are a problem.

Wires a bit long, stock length of esc and batteries, no adapters.
so 2 deans, 10g wire all around 40c on 8000mah 90c on 7400 mah

We will go with about 4in for batts 5in for esc leads

[srislash]

The Deans plugs could be an issue that heat the caps up. They really don’t flow too much amperage. Perhaps go to 5.5 bullits or maybe the Castle 6.5’s. Also shorten the wires as much as you can. I try to leave my batteries at a decent length and shorten the ESC on a boat per boat basis.

[justafatman]

The Deans plugs could be an issue that heat the caps up. They really don’t flow too much amperage. Perhaps go to 5.5 bullits or maybe the Castle 6.5’s. Also shorten the wires as much as you can. I try to leave my batteries at a decent length and shorten the ESC on a boat per boat basis.

ok, thank you for the advise!