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5s, 9L and x637 could/will either blow a esc or motor.
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Steven Vaccaro
Where Racing on a Budget is a Reality! -
why is that STeve? I ran the the ammo 2600 on 6's no issues with a 645..I thought I'd try the Feigao 9l because is has a slightly larger can with a smaller prop, how about a 632Last edited by RCprince; 12-18-2007, 04:11 PM.Samuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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That motor on 6S is going to turn at least 57,720RPM at the nominal voltage... fully charged, we're talking about 65,520RPM... That's NUTs, and isn't going to live long at all... It's going to pull MASSIVE amps... and even if you are running a Neu motor, which is rated at a max of 60,000 RPM, you're going to be KILLING motors off regularly... I find it rather hard to believe that you were able to run the 2600KV Ammo on 6S and it survived... the 2300KV version is what we use for 4S and it has to be VERY water cooled to do it... Are you SURE you are running 6S??? (22.2V Nominal??)
A proper 4S setup in a 30" hull should easily be capable of running into the upper 50's in OVAL trim... The RPMs you are turning are on the extreme even for a pure SAW setup...
If you want to run 6S, then you need to select the proper motor that will get your RPMs right... Target 30,000-35,000RPM for a boat like this... You need something in the 1600KV range to get it right... A 10XL or 11XL would really do the trick and let you turn a really decent sized prop... Would also be MUCH easier on the ESC... and would give you the right RPM for the application... ( the 10XL would be around 37,000RPM @nominal)...
I would think that either of those on 6S should be capable of 50's... without destroying any equipment...
Just my 0.02cents...Darin E. Jordan - Renton, WA
"Self-proclaimed skill-less leader in the hobby."Comment
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Just a lil final touches..lol yea rightSamuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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Your 0.02 cents is worth a lot of dollars in my book....thanx for the rundown..but yea I did run a few times an ammo 2600 on 6's after fully charged, thats how I got the 52 mph before it went airborne. Well I'll try it on the 4's..what prop do you think I should run with the 9l on 4's...ThanxSamuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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On 4S, you are still looking at around 43,696RPM... figuring 4V/cell loaded (might be more like 3.9V/cell... so maybe closer to 42,120RPM...)... Personally, I'd opt for something with a lower KV for this application... even for Oval racing.... Something in the 2300KV range preferably... and that may be considered "hot" on 4S by some standards...
Your 9L is doable, though still "rigger" RPM range... You'll need to keep the prop small.... I would think an X637 might be an OK place to start... You may end up at an X438... I'm not really a prop expert when it comes to giving this type of advice... I would think Jay Turner or someone with his intimate knowledge of Cats would be a better source for a recommendation...
If it were me... I'd start with an X438, or maybe an ABC 42x55, or maybe the Grim 36x55 (same pitch as the 42x55, but smaller in diameter...)... and go from there... I think there are some prop-calc tools somewhere here that one can use to get a closer recommendation...
I run a Neu Motor of about that KV (2700KV) in my 26" DH Mono on 3S2P using an ABC 42x55 at around 32,000RPM and the boat heat races all day in the mid-40's... I think it'll go into the 50's in the straights if I put more prop on it... Temps are great, boat is light... batteries are MUCH CHEAPER....
I don't even think I needed the 2P part, but I do it because the hull needs the weight and it's easier on the cells... Of course, the Nue is a more efficient motor with more torque, so it's not a one-to-one comparison KV wise... You'll likely be better off with 4S on that 9L...
I hope this helps some... I just want you to have as much FUN as possible, and as few "crispy pieces" as we can manage!
Last edited by Darin Jordan; 12-18-2007, 04:39 PM.Darin E. Jordan - Renton, WA
"Self-proclaimed skill-less leader in the hobby."Comment
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Exactly how long of a runtime did you do with a 6s and the 2600? From the sounds of how you described the run, it sounds like less than 10 seconds or so. If thats the case, thats the reason you didnt see any problems for heat build up.Steven Vaccaro
Where Racing on a Budget is a Reality!Comment
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Correct Steve, we would just do about 300 - 500 feet hole shots, wait a few seconds then go at it againSamuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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... Just went an looked... I would think a 10L (~2400KV) or maybe even an 12L (2040KV) would be a much more efficient setup... 12L would give you around 32,000RPM and should run for a long time, draw lower amps, and be very easy on equipment... Should also be capable of some pretty fast speeds... I guess it'll depend on what you are after... for all-out Oval racing, I'd have choosen the 10L I think... but again, I'd defer to Jay Turner or someone with his experience...Darin E. Jordan - Renton, WA
"Self-proclaimed skill-less leader in the hobby."Comment
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Darin since I got back into Rc's in april- may..I have lol torched no lie let me see
1 CC griffin 55 -74.00
3 Electrifly's 35amps 120.00
Now Brushless
5 Suppomodel esc's ranging from 60 amps -100amps 29.00 to 44.00
3 e-flite 60amp pro switch. 74.00 ea
proboat BJ esc ?
Hacker 70 amp xpro 119.00
Align 75 amp 90.00
I could have bought a jeti spin 200amp by now.....I look at it this way I could be doing drugs, alcohol or chasing women...But I indulge my self in Rc Boats....Samuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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Yah... it works that way sometimes.... but we'll get you pointing in the right direction...
Since you already have the 110HV coming... I wonder if maybe you could just get yourself a different motor and go ahead and run the 6S??? You'd pull lower amps than on 4S with the right motor... maybe a 11XL on 6S1P... which would give your around 34,000RPM... Since you already have the cells, and apparently have already purchased the ESC... this would just cost you another $70.00 for the motor... Same "power potential" as a 3S2P setup, but fewer amps... I think the higher V, less Amps setups are also more efficient, so it should run pretty cool, and would turn a healthy wheel...
All kinds of options really...Darin E. Jordan - Renton, WA
"Self-proclaimed skill-less leader in the hobby."Comment
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Yea my replacement 110 is coming, mine stop working, just the light comes on and it links with the cc link but no motor tones...so they're sending me a replacement....Yea I'm gonna look into one of those XL's of a KB the KB might be a lil to heavy though....Samuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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I just saw this 8XL on RRR that you might want to look at... That'd work well on 4S...
Darin E. Jordan - Renton, WA
"Self-proclaimed skill-less leader in the hobby."Comment
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Cool thanxSamuel Johnson - “An injustice anywhere is an injustice everywhere.” William Cooper "listen to everything, read everything, and believe nothing unless you can prove it in your own research!"Comment
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Sorry to jump in here. I am running the ammo 36-50-2300 right now on 12 cells. If I was to go to try a 7xl which is a 2384kv I think, I should be able to pull a larger propeller since the motor should have a bit more tq.
RCprince, the boat looks great by the way. Lets see how close to 60 you can get her.Last edited by obrien; 12-19-2007, 12:10 AM.Comment
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