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Old 12-23-2003, 10:05 AM   #31
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Quote:
Originally posted by DynoMoHum

I'll say it once again.... AMP numbers at low voltages with no load on the motor... are not all that usefull in determining the proformance of a motor... At least not without knowing a lot of other stuff to go with that bit of information. I'll give you a couple examples of why I say this, the first is a bit extreeme but important... The second is a bit more realistic of what you might see that could confuse you...

First... go wedge a e-clip inbetween the armature and the magnets of one of your motors, apply 2 volts and see the amp draw go to the moon... (I said it was extreeme) Ok, so don't do that, it's stupid... but think about what would happen if something in your bushings was causing your motor to have some binding, your amp will go up, and your proformance will go down.


my basic stament about no load amp draw... 'BY ITSELF, it means very little'.
How true, a few weeks ago a young racer at the track was checking out a few motors on his T35, spinning them up at 5 or 6 volts to see which was his best...... and he got all excited like "WOW this one is gonna be hella fast cause the amp draw shut mt T35 down!!!" So I had to prove to him that the motor wasn't necessarily gonna be his best preformer...... I took his lowest amp draw motor, turned the voltage down to 2 volts, clamped a pair of vicegrips to the shaft and told him to start the motor run...... It shut the T35 down in less than a second!!! So I said "WOW this motor is probably even better now!!!!" LOL
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Old 12-23-2003, 05:45 PM   #32
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Yeah, I have motors shut down my T35 at 2.5 volts.
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Old 12-23-2003, 09:56 PM   #33
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Default Dyno numbers don't mean anything!

Guys;

I'm sure that 'Trinity' does actually Dyno the "Pro" Motors as they claim (or it'd be false advertising) and that the sticker on the Motor is from an actual Dyno run. It probably just does NOT belong on THAT particular Motor
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Old 12-23-2003, 10:02 PM   #34
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No it's just that the "Motor Builder's" aka "Production" version of the Facts Machine software reads anywhere from 4-6 watts high, and Trinity uses that software. A friend and I have tested that.
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Old 12-23-2003, 10:11 PM   #35
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I believe the dyno sheet does belong to the motor it is on.... however if Fantom shows better numbers with higher RPM then that could also be a very good reason that Big T doesn't full break in the motors... brushes that aren't broken in properly would have less contact area and thus higher RPM.... and in turn higher numbers!!!

Personally I don't care I buy the pro motors because they have the equiptment in them I want (red/green springs and 4499 brushes), and if they aren't properly broken in then I can cut the comm myself and reuse the brushes too..... bonus for me....LOL
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Old 12-24-2003, 10:20 AM   #36
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I'm curious here... I've wanted a dyno to do my own motors, and friends also... Is everyone fixated on peak numbers or how the motor performs over its entire RPM range????
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Old 12-24-2003, 10:34 AM   #37
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You have to look over the whole RPM range because that will tell you where the motor is strong how to gear the motor.
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Old 12-24-2003, 10:40 AM   #38
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Default Dyno numbers

IMPACTPLAYR;

Aftermarket tuners such as Fantom, etc, process a much smaller quantity of Motors than Trinity. For this reason you can be reasonably sure that the Dyno sticker matches the Motor when purchased from a tuner.

Guys;

As some others have said, I personally find that the numbers produced by a Dyno pull at 5volts, do not accurately represent what you would be getting with a 6 cell pack in your Car. This is one of the reasons why some of us have chosen the Robi over any other brand of Dyno.
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Old 12-24-2003, 03:47 PM   #39
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Default Re: Dyno numbers

Quote:
Originally posted by popsracer
IMPACTPLAYR;

Aftermarket tuners such as Fantom, etc, process a much smaller quantity of Motors than Trinity. For this reason you can be reasonably sure that the Dyno sticker matches the Motor when purchased from a tuner.

Umm I am absolutely sure you are correct about the smaller tuners like Fantom.... HOWEVER I was responding to what was said about TRINITY not a small company by any means!!
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Old 12-25-2003, 02:02 PM   #40
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Yes many people do get too hung up on peak power numbers, and they really don't tell you too much about the motor's overall proformance. You really do need to look at the motor's proformance over as much of the RPM range as you can. This really is probably the only reason need given as to why Dyno Lables don't really mean much... THat is, typicaly all they give are peak numbers, and it really is hard to learn much from peak numbers alone.


CE TurbroDyno sheets don't give peak numbers, however they too can be hard to relate to on track proformance as well...

The Robitronic can produce a sheet that gives more then peak numbers too. I'm not sure I've ever seen one myself, other then an example they give in the manual. Alternnitively you could print off a full color graph from a lap top when useing the Robitronic, but that's probably not something you'll see very often in a 'pro' motor.
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Old 12-25-2003, 05:31 PM   #41
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The Fantom does allow you to print off a very useful printout which reads off the info for 6-8 rpm readings

Looks kinda likethis is not in any way factual just hypothetical)

RPM- torque- amp draw-EFF%
11000- 68- 15- 89%
15983- 89- 23- 92%
20257- 94- 36- 86%
24873- 109- 32- 73%
29254- 103- 27- 69%
33769- 90- 20- 57%


AGIAN this is all hypothetical and made up, however this is the print out that can be made with the fantom..... for all the faults that you guys have with the fantom it still has the most useful printout capabilities.... BUT this has to be printed on a sheet that is too big to go on any label for the motor.....


If you don't believe me just buy a Fantom tuned motor!!!
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Old 12-25-2003, 07:10 PM   #42
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Quote:
24873- 109- 32- 73%

In my way of thinking, this would be the most important number for me... We're running on road tracks here... Numbers that equate to high HP readings don't really mean much... I'm interested in the peak torque and to gear the motor to take advantage of that... Let's face it, you're spending much more time in the corners and accelerating out of them then you are runnng down the straight...
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Old 12-25-2003, 07:25 PM   #43
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Well, once again, I have to question the accuracy of the numbers the fantom is giving... as far as I know, peak torque on these electric motors should occur at 0 or 1 RPM...

Oh, those are hypathetical numbers...


buy anyway peak torque should occure at start up of the motor, and go down pretty consistantly till the motor reachs max RPM.

Power will peak at something close to 50% of max RPM...
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Old 12-27-2003, 01:42 PM   #44
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Quote:
Originally posted by IMPACTPLAYR
The Fantom does allow you to print off a very useful printout which reads off the info for 6-8 rpm readings

Looks kinda likethis is not in any way factual just hypothetical)

RPM- torque- amp draw-EFF%
11000- 68- 15- 89%
15983- 89- 23- 92%
20257- 94- 36- 86%
24873- 109- 32- 73%
29254- 103- 27- 69%
33769- 90- 20- 57%


AGIAN this is all hypothetical and made up, however this is the print out that can be made with the fantom..... for all the faults that you guys have with the fantom it still has the most useful printout capabilities.... BUT this has to be printed on a sheet that is too big to go on any label for the motor.....


If you don't believe me just buy a Fantom tuned motor!!!
i was gonna say.if a dyno print out had

rpm 23,000
torque 95nm
eff 65%.
this is one of my monster stocks and the numbers arent bad .
but on a small track [very very small,the monaco of rc tracks]
i was beat in the heats with an mvp non pro and the numbers on that were something like

rpm 20,000
torque 105nm [!]
eff 70%

this was on the same dyno.even though the monster seemed a lot better on the dyno rpm wise and was only 10 nm torque more were as i had 3000 rpms more they were evenly matched.
our overoll gear ratios were almost the same i had 8.7 and he had 8.0 he still pulled a lot more then me.
in the final i was 2nd in da a-final and put my good mvp in which was rated at
rpm 2100
torque 113nm
eff 61%

i then had the upper hand and actully overtook pulling out of a corner.
this shows that dynos can be a small guide but not just a black and white pic.
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Last edited by trf racer; 12-28-2003 at 04:16 AM.
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Old 12-27-2003, 05:05 PM   #45
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I'm going to guess that 20,000 not 2000....


He was out accelerating you because he had more torque at a lower RMP... You had to spin up 3000 more RPM and you still didn't have as much torque... On a tight track, his motor is a much better choce... You'd have to gear higher to match him, havng equal rollout definitely gave him the advantage... You'd have been better off with a ratio over 9.2 to take advantage of the added RPM.... In my eyes your motor's numbers weren't better than his, I'd have used his in a heartbeat...

Did you stay with the same rollout? Your second motor was definitely better, there was only a 1000 RPM gap and from what you posted you had a slightly higher rollout to take advantage of it...

The dyno read fine, it was more like you didn't see the whole picture...
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