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  1. #1
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    9800kV LRP 3S A123 979Watts

    I just plugged in x10 and x11 LRP motors in the Rustler. Having a mean Hybrid Sensored ESC, I figured to run a high kv motor in the Rustler. All this talk about how the 9000kv Mamba won't work in a Rustler had yet to be proven.

    Just to let you new schoolers know. I had ran the 4.5 LRP a while back with the mamba and it works. However it only worked properly if you eased into the throttle, but once it was moving it moved hard. With the 3.5 LRP in sensored mode, I was able to creep the Rustler.

    So here's the setup
    LRP 3.5 9800kV, 12AWG wires
    3S1P A123
    58/12 gearing
    Proline Dirt Works
    200A Hybrid Sensored ESC

    Did a few high speed passes and used up 1800mah in 4 minutes and 19 seconds.

    Peak 171.86A
    Voltage dropped to 5.15V
    Peak 979W

    During a high speed pass, the system was pulling 122.11Amps at 6.21V, which is 758Watts.
    So to those going with a 9000kv motor, beware not to use a cheap battery pack.
    2 KILOWATT RACER

  2. #2
    RC Turnbuckle Jr.
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    These still confuse me, but they are cool all the same. I, like most others that aren't as well versed on how to read those graphs, put my faith in the almighty top speed.
    An injured friend is the bitterest of foes

  3. #3
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    Just figure it's about 1HP and in the mid 50's with that low voltage.
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  4. #4
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    So if that setup is about 1 HP, why is my VXL on 6 cells faster than my old RC10GT with a Megatech m-16 1 HP motor?
    RustyVXL, HPI RS4 Rally, RC18MT
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  5. #5
    RC Turnbuckle Jr. Dadx2mj's Avatar
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    Quote Originally Posted by StamJato
    So if that setup is about 1 HP, why is my VXL on 6 cells faster than my old RC10GT with a Megatech m-16 1 HP motor?
    Come on man EVERYONE knows anything from Traxxas is faster than anythign from Associated , not to mention brushless is ALWAYS faster than nitro
    BlindMan Racing
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  6. #6
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    But if that hotrod setup is 1 hp, mine is probably half that. So why is my rig so much faster than my old one with more power? Just way more torque, so quicker accel with same top speed?
    RustyVXL, HPI RS4 Rally, RC18MT
    Mobius1 crashed!

  7. #7
    RC Turnbuckle Jr.
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    HP is not everything. You could have all the HP in the world, but that doesn't neccesarily mean good performance. If your engine doesn't have a viable band of peak torque, HP doesn't really matter that much any more. Like those guys who took the Supras (poor, poor supras) and tuned their engines to 500-600 HP (yah, out of a little 3.6L V6). Sounds awesome doesn't it? But those things were dragstrip/dino wonders only, they made peak torque at the most awkward times. First gear would crawl, second gear would throw you into your seat, then third gear would be throbingly weak, and so on. Lol, guess this may not be the best example, but its all I could think of.
    An injured friend is the bitterest of foes

  8. #8
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    It must be the torque, because top speed seems close, but I don't remember my GT wheelying all over the place!! Whatever it is, AC motors rule!
    RustyVXL, HPI RS4 Rally, RC18MT
    Mobius1 crashed!

  9. #9
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    Quote Originally Posted by StamJato
    It must be the torque, because top speed seems close, but I don't remember my GT wheelying all over the place!! Whatever it is, AC motors rule!
    well u gotta remeber nitro will never have the torque electrics do
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  10. #10
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    Quote Originally Posted by VXL Beast
    HP is not everything. You could have all the HP in the world, but that doesn't neccesarily mean good performance. If your engine doesn't have a viable band of peak torque, HP doesn't really matter that much any more. Like those guys who took the Supras (poor, poor supras) and tuned their engines to 500-600 HP (yah, out of a little 3.6L V6). Sounds awesome doesn't it? But those things were dragstrip/dino wonders only, they made peak torque at the most awkward times. .
    H/P wins the race.... Torque launches you... Sorry VXL BEAST but this whole post is, well.....

    The supra mills are not V-6's there I-6- str8 6- or inline 6.. whatever you prefer to call them

    Dragstrip/dino wonders is what kills me...ROFL..
    Have a look and dont let your chins crack the keyboard..
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    Keep flex'in those forum keyboard muscles.

  11. #11
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    58/9 Gearing is perfect for the Rustler running this motor. I still pop wheelies if I'm not careful.
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  12. #12
    RC Turnbuckle Jr. rjm2519's Avatar
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    H/P wins the race.... Torque launches you... Sorry VXL BEAST but this whole post is, well.....
    Actually the saying is torque wins the race...at least the drag race. Hence the big blocks of the big three's hay days not suped up small blocks, for the most part anyway. It is actually all about the torque curve as mentioned above somewhere. DC motors dont build torque they build horsepower, torque is all there from the get-go that what makes them so much quicker than nitro's.
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  13. #13
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    OOPS. ^^darnet- shucks man.., i should have known i didnt know what i was talking about..
    Last edited by got_nitro; 12-09-2008 at 07:17 AM.
    Keep flex'in those forum keyboard muscles.

  14. #14
    RC Turnbuckle Jr. asheck's Avatar
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    Actually hp is( torque x rpm/1000000),so either can get it done,with the right gearing behind it.
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  15. #15
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    Did y'all know that on a dyno chart, TQ and HP will ALWAYS cross at 5252 RPM? I can't remember the equation, but something to do with converting TQ, which is just twist, to HP which is work over a given time. I don't think this applies to electric, but if anyone knows, speak up. BTW TQ can be applied to something that's not even moving. If you go up and try to twist a light pole with your hands, you are applying torque, even though no work is being performed. Any engineers care to shoot down my theories, or agree?
    RustyVXL, HPI RS4 Rally, RC18MT
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  16. #16
    RC Turnbuckle Jr. rjm2519's Avatar
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    But a flatter and higher torque curve will get it done quicker and faster.

    Stamjato you are correct torque requires no actual motion just force. An electric motor albeit a large one can put out 200lb*ft of torque from 0rpm, there are some guys building electric drag cars using forklift motors and hitting mid 11's in the 1/4mile, if I remember correctly.
    Last edited by rjm2519; 12-09-2008 at 11:10 PM.
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  17. #17
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    I just read a Car and Driver mag or R&T where they tested a new RUF prototype electric 911. It was a lot heavier than stock, because of all the batteries, but the thing put out 200 HP with 479 TQ if memory serves. Thing is, electric can make all it's TQ from 0 RPM, and this thing had the stock 6 speed manual. Talk about short shifting! Imagine lugging down to what would be stall speed in a regular 911, in 6th gear then punching it!! BTW it's Brushless Lipo. I want one!!
    RustyVXL, HPI RS4 Rally, RC18MT
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  18. #18
    RC Turnbuckle Jr. rjm2519's Avatar
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    I don't think I would be too inclined to sit in a high performance electric vehicle right now with any kind of batteries it just sounds entirely too dangerous.
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  19. #19
    RC Turnbuckle Jr. Dadx2mj's Avatar
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    Quote Originally Posted by rjm2519
    I don't think I would be too inclined to sit in a high performance electric vehicle right now with any kind of batteries it just sounds entirely too dangerous.
    LOL but a car with a tank full of gasoline is ok?!?!? Gasoline has a BTU rating 19X higher than that of TNT.
    BlindMan Racing
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  20. #20
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    Quote Originally Posted by rjm2519
    I don't think I would be too inclined to sit in a high performance electric vehicle right now with any kind of batteries it just sounds entirely too dangerous.
    The first car(s) ever made were battery powered and later Mr. Ford was using Ethanol. Batteries are very safe and getting safer each day. Please look at the following video: http://www.caleb-battery.com/caleb_nail_0001.wmv. A123 has the same safety feature as well as a few others. But you will see the occasional misuse that will basically set anything on fire.

  21. #21
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    Quote Originally Posted by rjm2519
    I don't think I would be too inclined to sit in a high performance electric vehicle right now with any kind of batteries it just sounds entirely too dangerous.
    It's only dangerous if you try driving it like you drive your electric RC!

  22. #22
    RC Turnbuckle Jr. rjm2519's Avatar
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    That is why I said high performance car, I am not talking about a hybrid prius...geez...pay attention.

    Dad when is the last time a gas tank exploded from being drained too quickly. LOL
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  23. #23
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    Um this is RUF we're talking about not some hillbilly. No offense if any of you are hillbillies.
    RustyVXL, HPI RS4 Rally, RC18MT
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  24. #24
    RC Turnbuckle Jr. Dadx2mj's Avatar
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    Dad when is the last time a gas tank exploded from being drained too quickly. LOL
    When was the last time you saw a battery explode from being drained too fast?
    BlindMan Racing
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  25. #25
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    I think he means over-discharged.
    RustyVXL, HPI RS4 Rally, RC18MT
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  26. #26
    RC Turnbuckle Jr. Dadx2mj's Avatar
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    Quote Originally Posted by StamJato
    I think he means over-discharged.
    Okay when was last time you saw a lipo battery explode from being over discharged?
    BlindMan Racing
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  27. #27
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    Isn't that the danger with Li-Po? Isn't that the reason for LVC? I dont know, I'm still in the dark ages with NiMh.
    RustyVXL, HPI RS4 Rally, RC18MT
    Mobius1 crashed!

  28. #28
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    That video is funny> The music cracks me up.
    RustyVXL, HPI RS4 Rally, RC18MT
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  29. #29
    RC Turnbuckle Jr. Dadx2mj's Avatar
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    Quote Originally Posted by StamJato
    Isn't that the danger with Li-Po? Isn't that the reason for LVC? I dont know, I'm still in the dark ages with NiMh.
    When lipos are over discharged it kills them as in they wont accept a charge again. I have never seen one blow up from being over discharged. Usually when a lipo goes up it is from being over charged or from being punctured or physically damaged in some way.
    BlindMan Racing
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  30. #30
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    Oh yes very interesting.
    RustyVXL, HPI RS4 Rally, RC18MT
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  31. #31
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    That's why they use a BMS (Battery Management System) which doesn't allow over charge or over discharge. It's kind of like our voltage cutoff, but it monitors all the cells the vehicle uses.

  32. #32
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    Quote Originally Posted by got_nitro

    The supra mills are not V-6's there I-6- str8 6- or inline 6.. whatever you prefer to call them :cool[/url]
    Huh, could have sworn the Supra engines were more of a conventional design. Anyways, they had some beatly potential, 400HP wasn't hard to see with just a little PSI increase.
    An injured friend is the bitterest of foes

  33. #33
    RC Turnbuckle Jr. rjm2519's Avatar
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    I still don't trust them (automakers not the batteries) , I am learning from your comments though and maybe some day I will take the lipo plunge but not now or anytime soon nimh are just too inexpensive to justify the extra cost, for me anyway.
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  34. #34
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    Very impressive numbers snellemin!

    I don't suppose you have a NiMH pack sitting around that you could run in that setup purely for comparison of voltage drop under that kind of load?

    BTW is that one of Lutach's esc's your running?
    [QUOTE=Billstmaxx]if the water can't get out how does it get in??[/QUOTE]

  35. #35
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    Quote Originally Posted by Just go Play
    Very impressive numbers snellemin!

    I don't suppose you have a NiMH pack sitting around that you could run in that setup purely for comparison of voltage drop under that kind of load?

    BTW is that one of Lutach's esc's your running?
    I'm proud to say, that it is lutach's ESC lol. Those numbers sure look impressive. I only managed 172A, but snellemin had to just beat me down lol. He's lucky is too darn cold here for me to use my 1.5T motor.

  36. #36
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    Quote Originally Posted by Just go Play
    Very impressive numbers snellemin!

    I don't suppose you have a NiMH pack sitting around that you could run in that setup purely for comparison of voltage drop under that kind of load?

    BTW is that one of Lutach's esc's your running?
    Don't insult me man

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