HELP with this 35" Catamaran (pro's & con's)

[RC fetish]

Hey guys (and maybe gals?),

Please

I could REALLY use some good advice on this 35" Catamaran with installed hardware (Pro's & Con's please)

CLICK ON LINK FOR FULL DETAILS & MORE PICS.... http://www.tobsd.com/ViewDetails.aspx?ProductID=738

I would like to run around 50mph
(give or take')

- I'm thinking of using Leopard 3674 3270Kv motors & matching water jackets that I'll purchase from OSE, and powered with 3S LiPo's
(I already have a bunch of 3S LiPo's)

- I'm thinking of using the newest version V2.1 Mystery UBEC 100A or 200A water-cooled ESC's
(I'll rebuild' them using Arctic Silver thermal paste & check all soldering)

- I'm totally lost' on which props to use ? Should I get a left & right, with both turning inward ?? 2-blade or 3-blade ???
(maybe Atomik's CNC 3-blade 36mm x 1.4P left & right? OR 2-blade left & right in-size they suggest in description??)

Does anyone have good/bad opinions on this boat... and my planned setup ??

I thank you VERY much in advance for your time & advice

P.S......
- I love the style/look of this Cat'
- I like the single & solid motor mounts, instead of the universal-all-in-one Balsa wood units I see some come with
- I like that the battery trays are in the outside-bottom, instead of in the center-top I see some come with (lower center of gravity is a good thing, correct?)
- I like the price for this ARTR (the hard-for-a-newbie' parts are already installed !!)
- I do NOT like having only one single water cooling inlet' to cool both motors & ESC's

[785boats]

I've built up a couple of TOBSD boats. Not that cat though.
From the pics it looks like the mounts are built in nice & solid.
For the motors you are using, a pair of 4214 props to start & I'd say you could go to 4514 when you've got it mostly trimmed out. Depends on the current draw & the heat with the 42's.

http://www.offshoreelectrics.com/pro...+2+Blade+Props

I have a 36" twin cat & have the props turning in at the top.
It runs two 4074 2200kv motors on 4s with the 45mm props & the motors are cold. As are the Turnigy 120A ESC's.
If you are going to use the Mystery ESC's go for the 200A ones. Always good to have plenty of headroom with that type of ESC. They are only a few bucks more.

Your 3s packs would need to be in the 5000mah 40C plus to keep things happy.

Here's my "Aquapassion" snatching a win from a failing tunnel hull on the line. Even after going stupidly wide in one corner & a flip in the back straight.

Cheers.
Paul.

[RC fetish]

Or maybe Leopard 3674 2200Kv 3D 4-pole on 4S LiPo ? (3250RPM)
Or like his above with Leopard 4074 2200Kv 2Y 4-pole on 4S LiPo ?? (3250RPM)

- Run 50MPH-give-or-take' without any heat issues ??
(I'm going' with the 200A ESC's)

ANY help PLEASE guys....

P.S. I thank you very much for your time' Paul !!

[devo]

I would buy 2 4074 motors and run it on 4s or 6s. Around 2000kv for 4s and 1700kv for 6s, and start with a pair of 440's and also go ahead and get a set of 443's and 445's. Im running a setup similar to this on a 41 fantasm on 6s and it screams, so you should have trouble keeping it from flying with the speeds you will be approaching. I personally like and own many t180 esc's and they can handle anything that you would put in that boat. you need to add another water pickup and run one line for each side, treat it like two different boats with your electronics so when you have an issue it's easier to isolate the problem

[kfxguy]

I would run t180 esc's. They are waterproof which is nice. And durable. I have a set of cnc props for sale, the same ones recommend to you above. I just posted them for sale last night.

[RC fetish]

2000Kv or 2200Kv... "that is the question"

Ok ok, sounds like I need to go with a pair of 4074.... BUT WHICH VERSION with 4S LiPo, the 2000Kv or 2200Kv ??
(both in-stock @ OSE)
- Are 4000mah or 5000mah 4S LiPo's with discharge' of 40C ok, or do I need to go with a higher C' rating ?

I don't need to run way-out-of-control-fast... as I'm really scared of flipping her !!

45-50MPH is about the fastest a RTR-not-dialed-in 35" Cat can "safely" run in 5-10mph wind conditions'... CORRECT ??

- I'm also trying to figure out what duel water pickup/outlet rudder to go with instead of the single' stock rudder ?
(OSE might be out-of-stock on the version I need)

AGAIN... in advance, I thank you all VERY much for your

Peace, Dave

P.S. Waiting for boat to arrive from China - only info I have is in the link in 1'st post

[785boats]

Dave.
If you are going to 4s instead of the 3s that you first posted, then definitely the 2200kv motors. But the 3s setup you posted first will work pretty well too.
The motors I use are TFL SSS 4074 2200kv, with a very slim TFL cooler. Similar to this, but a bit shorter.
http://www.offshoreelectrics.com/pro...prod=ose-80033
A 5000mah 40c pack on each motor will be plenty. Same with the 3s set up if you go that way.
We are not allowed to run dual packs here, so that video is with both motors running off one 5000mah 45C pack.
I don't know what speed it does. Just fast enough to win now & then.

Paul.

[devo]

If you go with the 2000kv motors you could always bump it up to 5 or 6s, if 4s isn't enough for you. I know there are alot of people on here that say 2000kv is too high for 6s but i've been running this setup in my river cat and fantasm for over a year now and have had no issues. If you only wanna go 50 mph the 200kv on 4s with some good 5000mah 40c batteries will do the trick. If you choose a hotter setup be very careful and check your temps after a short run every time you change the setup on your boat. My experience is that you can get away with higher kv motors with hotter setups on catamarans because there is alot less drag on that kind of boat than a V hull.m This is just my .02

[785boats]

But with twin motors sharing the load they can be pushed a bit higher in KV & prop sizes.