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Old 11-04-2014, 09:34 AM   #436
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John: ok so say at zero timing it does 20,000rpm and max timing it does 27,000rpm, you are saying it takes longer to get to 20,000 under max timing OR it takes longer to get to 27,000?
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Old 11-04-2014, 10:01 AM   #437
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Jay, you have to remember that when a motor is on a dyno it's like having it in a car with a non-adjustable gear ratio, fixed weight, and no aero resistance. A motor at high timing will have less bottom end torque and therefore will spin up slower due to having less torque to overcome the weight of the flywheel, it will take more time to spin up to its power band, and the machine will record this as having less torque and therefore less power at low RPM. BUT it will have more torque at the top end and will spin more RPM, so the peak power (torque*RPM)/(Power Constant) will likely be higher, at a higher RPM, and with less torque at that peak power number.

Think about it this way, a motor at an optimal high timing mark will have 20% less torque than a motor at low timing, but will make peak power (with 20% less torque) at a 30% higher RPM number. By running a 20% lower gear in the car, the car still accelerates as fast as the lower-timing setting, but because it can spin 30% more RPM, you gained top end power and speed.

So the answer is yes, it will take longer to get to 20,000 AND longer to get to 27,000, but in doing so it will have done more work (extra 7000 rpm) to get there and the machine will have recorded more peak power and more area under the curve, making the high-timing setting better (on paper) than the low timing mark.
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Old 11-04-2014, 01:23 PM   #438
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Pick a RPM, let's say 13,000. Set timing to 2. See how long it takes to reach RPM. Move timing to 4. See how long it takes to reach RPM. Draw your own conclusions from there.
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Old 11-06-2014, 11:55 AM   #439
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Sorry,what about 12.7 stator in 13.5 plutonium?

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Old 12-03-2014, 07:44 PM   #440
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What kind of performance gains, if any, might I expect it I were to put a 12.5mm rotor in my plutonium 17.5? Stock is 12.3mm. The motor is already a beast, but a little extra never hurts..
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Old 12-03-2014, 09:22 PM   #441
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Originally Posted by big al View Post
What kind of performance gains, if any, might I expect it I were to put a 12.5mm rotor in my plutonium 17.5? Stock is 12.3mm. The motor is already a beast, but a little extra never hurts..
You will see a noticeable increase in torque.
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Old 12-04-2014, 01:59 PM   #442
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Quote:
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John: ok so say at zero timing it does 20,000rpm and max timing it does 27,000rpm, you are saying it takes longer to get to 20,000 under max timing OR it takes longer to get to 27,000?
Sort of both. The plot line (rpm Vs time) crosses for zero timed and max timed motors. For my 21.5 TPS Motor (same motor dynoed at at different timing), initially from a dead stop the zero timed motor accelerates faster than the max timed motor. Then the lines cross over at ~0.4 seconds and from that point on the max timed motor accelerates faster. The max timed motor does get to the max RPM of the of the zero timed motor (10.5K RPM @ 5V) about 1/2 second faster than the zero timed motor does, but still takes another 2 seconds to get to its max RPM (15K RPM @5V).

Last edited by John Wallace2; 12-04-2014 at 02:23 PM.
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Old 12-04-2014, 03:08 PM   #443
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Originally Posted by John Wallace2 View Post
Sort of both. The plot line (rpm Vs time) crosses for zero timed and max timed motors. For my 21.5 TPS Motor (same motor dynoed at at different timing), initially from a dead stop the zero timed motor accelerates faster than the max timed motor. Then the lines cross over at ~0.4 seconds and from that point on the max timed motor accelerates faster. The max timed motor does get to the max RPM of the of the zero timed motor (10.5K RPM @ 5V) about 1/2 second faster than the zero timed motor does, but still takes another 2 seconds to get to its max RPM (15K RPM @5V).
Just curious, does the dyno put the motor under any sort of load?
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Old 12-04-2014, 03:34 PM   #444
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Just curious, does the dyno put the motor under any sort of load?
Judging from the numbers he mentions it sounds like a flywheel dyno so yes, the load of trying to accelerate the flywheel.
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Old 12-04-2014, 03:44 PM   #445
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So what is the difference between the PLUTONIUM v2 and the Actinium motor? 12.3 vs 12.5 rotor and that's it?
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Old 12-04-2014, 05:49 PM   #446
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So what is the difference between the PLUTONIUM v2 and the Actinium motor? 12.3 vs 12.5 rotor and that's it?
Actinium is roar legal. The other isn't. You want the actinium....
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Old 12-04-2014, 06:38 PM   #447
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Quote:
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Just curious, does the dyno put the motor under any sort of load?
Yes its the Fantom Dyno (AKA Facts Machine II not to be confused with the Facts Machine 2) with the aluminum flywheel.
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Old 12-08-2014, 05:29 PM   #448
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Bought a Plutonium V2 and put it straight on a motor checker and the A/B/C sensors were way off.. Really bad. Like ~20 degree discrepancy between sensors. Has there been issues with the V2 sensor boards before? I took it out on the track and it hauls like no other motor, but a little concerned with the sensors being off.

Last edited by EDWARD2003; 12-09-2014 at 03:37 PM.
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Old 12-09-2014, 02:29 PM   #449
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Bought a Plutonium V2 and put it straight on a motor checker and the A/B/C sensors were way off.. Really bad. Like ~20 degree discrepancy between sensors. Has their been issues with the V2 sensor boards before? I took it out on the track and it hauls like no other motor, but a little concerned with the sensors being off.
20 degrees that's horrible, I was complaining about 4 degrees.
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Old 12-10-2014, 01:09 PM   #450
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I've had some way off too (not team Powers stuff). Won't menti0n who, but I just ordered a couple of new sensor boards, hopefully one of those will have the sensors better aligned.
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