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Old 02-19-2004, 03:54 PM   #1
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Default Electric Motor Dyno Comparision (was Need help comparing...)

I just picked up a Monster HP Pro and compared it to my P2K Pro.

The dyno number on the two cans were very similar in power and torque, but the Monster could make like 21k RPM versus some 18k RPM for the P2K.

It was my understanding that the P2K is a "torque" motor, whereas the Monster is more an high-RPM motor. But it appears, when comparing these two motors, that this particular Monster is just plain *better* than this P2K.

Does this sound reasonable? Should my P2K be shelved in favor of this new Monster? Or is there something else that I'm missing by looking at these numbers (such as power bands, etc?).

I'd love to see dyno output for these two motors, including charts of their power bands. I'm sorry to see that Trinity doesn't provide such detailed information on their web site.... is there anywhere else I should look?

Thanks,

Torsion

Last edited by Bob Nilsen; 02-20-2004 at 04:00 PM.
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Old 02-19-2004, 07:06 PM   #2
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its very possible that the Monster could have more torque too. RPM numbers don't mean a while lot because they can be easily manipluated. I used to get my Slot Machine 2's to turn over 23,000 RPM on a Tekin Dyno. Pretty awesome, right? Well, that same high RPM motor had absolutely zero torque, so it was a dog off the corner. Unfortunately you actually need a dyno to test the motor and get actual numbers.
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Old 02-20-2004, 08:22 AM   #3
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Drive them both and see what you think. Thats the best way to tell. You may have to gear them differently however as from what I understand the monster is a high RPM motor.
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Old 02-20-2004, 03:59 PM   #4
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Thanks a lot for the help, y'all.

One more thing... does anyone have explainations of all the parameters on a dyno readout?

RPM - Top speed (unloaded?)
Torque - maximum torque (is this from a dead stop?)
Power - is this the maximum power draw of the motor?
Efficiency - Why is this one even that important?
(isn't there one more?) -
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Old 02-20-2004, 10:11 PM   #5
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RPM= revolutions per min.
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Old 02-21-2004, 10:34 PM   #6
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Dynos have flywheels that are atacted to the motor. the flywheel has holes in it that is picked up by the dyno. Torque is mesred by how fast your motor gets to top speed. Power is torque and RPM together, its like horsepower. Efficiency is just how much of the power going to the motor is being used vs. how much is making heat not power.
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Old 02-22-2004, 01:46 PM   #7
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What kind of car are you running? Usually you want to gear the monster two too three teeth lower from my experience. I have mine two lower and it runs warm, no where near hot. SHoot me back a response on which car you are running, and i may be able to help you out a little more.
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Old 02-22-2004, 01:47 PM   #8
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I'm in a rustler with the stock 84-tooth spur.

Thanks for the help!
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Old 02-22-2004, 10:12 PM   #9
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I'm in a rustler with the stock 84-tooth spur.

Thanks for the help!
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Old 02-23-2004, 08:58 AM   #10
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What size pinion were you running with the p2k? The it will give me a base to help you out.
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Old 02-23-2004, 10:27 AM   #11
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I had nice runs on our course with a 16T, with the P2K staying cool, and I haven't had a chance to try a 17T pinion yet.
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Old 02-23-2004, 11:59 AM   #12
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Hmmm, well try goin with a 14 tooth pinion with the monster, since its a higher rpm motor, you need lower gearing to acheive the whole powerband. IF it does not get hot, or seems like its slow, then you should have to change gearing. But 14 is about where you should start, assuming the info you have given me about the p2k.
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Old 02-23-2004, 08:55 PM   #13
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Thats just about right with a 84 spur. try using a 87 / 21 with your P2K and a 87/20 with the monster. With the right gearing you should just barly be able to hold the motor for 5 sec. Your racing right? Dost have pede tires on it?
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Old 02-24-2004, 11:47 AM   #14
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Yes, I'm racing... and No, I don't have stampede tires on it.
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Old 03-02-2004, 10:20 PM   #15
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Just something to think about, Trinity's rpm and torque specs are @ 5 volts. At 8+ volts on a fresh charge that Monster HP should turn way faster than 21k.
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