JayL

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?

DesertRat

iTrader: (2)

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.

Advil

iTrader: (19)

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.

Pigiolino

Sorry,what about 12.7 stator in 13.5 plutonium?

Pigio

big al

iTrader: (10)

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..

Gridworks Racing

iTrader: (3)

You will see a noticeable increase in torque.

John Wallace2

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).

erchn

iTrader: (7)

Just curious, does the dyno put the motor under any sort of load?

wingracer

iTrader: (24)

Judging from the numbers he mentions it sounds like a flywheel dyno so yes, the load of trying to accelerate the flywheel.

tobyzhang

iTrader: (15)

So what is the difference between the PLUTONIUM v2 and the Actinium motor? 12.3 vs 12.5 rotor and that's it?

hanulec

iTrader: (28)

Actinium is roar legal. The other isn't. You want the actinium....

John Wallace2

Yes its the Fantom Dyno (AKA Facts Machine II not to be confused with the Facts Machine 2) with the aluminum flywheel.

EDWARD2003

iTrader: (8)

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.

b20btec

iTrader: (11)

20 degrees that's horrible, I was complaining about 4 degrees.

John Wallace2

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.