Originally Posted by bertrandsv87

The whole point of motor tuning is to find the sweet spot of only the motor you are testing at the time you are testing it. Compare two different motors on the same track layout to see which one lowers your laptimes on that layout, but it does not mean that the slower motor on that layout will stay slower on a different layout. At some point the track performance will rule over spread sheets, and you'll need to make the correct choice of motors for the layout of the race...

Originally Posted by OffRoadJunkie

True, a higher torque motor can draw more amps. But then you're pulling a lot more heat. It's like adding a 2000 gauss rotor to a 17.5 stock motor. You'll get a lot of torque, but it gets too hot to race. About 99% of the racers out there will gear their motors until they hit the brink of thermal meltdown. Motor that draws too many amps will generate too much heat which will greatly limit your gearing.

As for efficiency and torque, efficiency turns into more usable torque. With stock motors having so many regulations, and after testing roughly 20 motors over the past few years, I found efficiency does end up meaning the motor has more torque. Also, while I was working for VIA Motors, as a sub-assembly Supervisor, to find the torquier motors, we looked efficient running motors.

With IC motors, RPM doesn't really determine what motor has more torque, but I don't think I am fully understanding the comment. However, a 5.0L diesel will have more Torque than a 5.0L petrol motor. The diesel is also a lot more efficient.

Anyhow, this is very complex conversation that cannot be discussed in a chat room. A lot of questions and examples need to be shared in order to understand what both of our thoughts are, on this topic.

Originally Posted by gigaplex

RPM drastically affects the torque output of an IC motor. Putting 2 different motors under the "same load" could put the motor way out of it's torque band, making it look like it has poor torque, when really it might have way more peak torque at a different RPM. You often need to put them under different loads to compare them. The Jerry only tests the steady state where the RPM is at equilibrium.

Originally Posted by OffRoadJunkie

True, a higher torque motor can draw more amps. But then you're pulling a lot more heat. It's like adding a 2000 gauss rotor to a 17.5 stock motor. You'll get a lot of torque, but it gets too hot to race. About 99% of the racers out there will gear their motors until they hit the brink of thermal meltdown. Motor that draws too many amps will generate too much heat which will greatly limit your gearing.

Originally Posted by Mac The Knife

Well Giga, you gotta start somewhere, and since I don't have a motor dyno, and you don't offer anything up other than arguments, I'll use OffRoadJunkie's findings as a starting point, and use the datalogging of my esc with the car on the track to make any adjustments from there.

Originally Posted by gigaplex

Peak power is usually at half of the no-load RPM. So, measure the no-load RPM, then adjust the gearing with the slave motor to make the master motor run at half of that RPM. Measure the output RPM of the slave motor. Repeat the process with the motor you're comparing against. The motor with the highest peak power should be the one with the highest RPM of the slave motor.

This is still just an approximation though, you need a proper dyno to be accurate as peak power isn't guaranteed to be strictly at the half RPM mark. You can still use it as an estimate for a starting point, and gear up/down slightly to see if you get any increases in the slave output RPM.

Originally Posted by gigaplex

My recommendation for using The Jerry as posted in a different thread:

Originally Posted by gigaplex

RPM drastically affects the torque output of an IC motor. Putting 2 different motors under the "same load" could put the motor way out of it's torque band, making it look like it has poor torque, when really it might have way more peak torque at a different RPM. You often need to put them under different loads to compare them. The Jerry only tests the steady state where the RPM is at equilibrium.

Originally Posted by G-rem

Very interesting point, so let's say I put a mod motor in a 21.5t stock motor, for the same ratio and ESC tuning, it will always run hotter then ?

Originally Posted by OffRoadJunkie

So,
I got the Team Powers V6S on my bench. It turned out to be a dud. While adjusting the timing, when I reached 40*, the motor didn't have enough torque to finish the Autorun cycle, with the Tunalyzer, while on the Load Master. At $175, with tax and shipping, this is the most I have ever spent on a motor. I really hope they have a warranty on this.

Originally Posted by Mac The Knife

I don't have a "Jerry", or a Tunalyzer, and the majority of us don't either. I do have a SkyRc analyzer, so what OffRoadJunkie provides for information gives me and others a starting point.

Originally Posted by OffRoadJunkie

So,
I got the Team Powers V6S on my bench. It turned out to be a dud. While adjusting the timing, when I reached 40*, the motor didn't have enough torque to finish the Autorun cycle, with the Tunalyzer, while on the Load Master. At $175, with tax and shipping, this is the most I have ever spent on a motor. I really hope they have a warranty on this.

Originally Posted by bertrandsv87

They'll probably send you a new one...