I was just curious about how much power this thing has if compared to a full-size 1:1 vehicle and decided to do a little number crunching.
The 1717 motor has a continuous power rating of around 2000w. Since the car weighs 10.3 lbs, that's a power to weight ratio of 0.2604HP/lb. If this was a 3,500lb car, the power would scale up to over 900HP average.
Now, 2,000w is "only" 90A @ 6s. Since we all know peak currents are always much higher, using an estimated 200A peak current draw equates to 4,440w. Scaled up, that's over 2,000 peak HP.
Assuming the use of the tallest possible gearing (46T spur/34T pinion), the tires are 4" in overall diameter (not sure about the exact value), and the current draw is 120A, the torque at the axle is a little over 2ft-lbs, which is 0.2ft-lbs/lb torque to weight ratio. Scaled up to a 3500lb car, that would be over 700ft-lbs of torque at the axle.
And if using the same 200A peak current value, peak torque at the axle is 3.43ft-lbs. Scaled up, that's 1,165 ft-lbs of peak torque at the axle.
So, if people want to know what driving one of these would be like, taking a spin in something with more power/torque, and have that power available right off the line, than a Bugatti Veyron would give you a rough idea.
Last edited by BrianG; 12-28-2011 at 11:13 AM.
Now that was fun.
I'd say this is a very good cost to value ratio, other than not actually being behind the wheel. Lol
Power doesn't really scale all that well. Your 2000 w number sounds reasonable. I've seen peaks on data logs too, but that doesn't mean that same force was exerted. The peaks are just that, a momentary spike.
The real fun will be all the actual data logging we will get out of the car. I'll be getting the GPS module, because we all know wheel rpm is often higher than ground speed with RC. Let's get some 0-60 averages from multiple people and do the math on how much energy was actually put to use.
About the peaks; it's the same as those peak HP/torque figures on 1:1 cars - they are very momentary. But while peak power arrives in the upper rpm ranges of a gas engine, brushless motors get their peak torque right off the line, so it "feels" like more power.
Given the acceleration of this car, which would be insane in the 1:1 world, those scaled up figures are probably pretty darn close. But, this was just for fun and not to be taken seriously.
Good job BrianG..that was cool
FLM E-MAXX 3908 6s
Rustler VXL x 2 MMP SCT 3800
Bugatti Veyron anyone?
Oh, and just want to point out that the Veyron wieghs 1888kg, which is 4162.32lbs. So, applying the X0-1's calculated power-to-weight ratios to a 4100lb car would be even stronger.
And, since the X0-1 is roughly 8th scale in size and does 100mph, that's a scaled up speed of 282mph...
Traxxas should scale this up and get into the 1:1 full scale car business, they have the R&D team and years of experience.