So quick in fact that i think i can beat the 0 60 time of a tesla roadster, making it one of the quickest electric vehicles in the entire world. So in this video we’re going to answer the question, can a toy really beat a real tesla and i should say that this acceleration is only made possible by these two electric jet fans that literally suck the car to the ground, creating an immense amount of downforce? Now, before we find out, if it actually can beat the tesla let’s talk about why it is really hard to do so and why i broke so many parts trying Music Applause first off, i have to exceed 2 g’s of acceleration to come close to the 0. To 60 time that i’m, going for and as newton taught us, this means i need a traction force equal to the car’s mass times, acceleration, which is about 16 pounds. Then i have to add in wind resistance and rolling resistance, giving me around 20 pounds to overcome the wheels have a 2 inch radius, which gives me a max moment of 40 inch pounds and at 60 miles an hour. They need to rotate at 5042 revolutions per minute, which is roughly equal to 2 400 watts to the wheels so obviously, i’m gon na need a much more powerful, 6s motor setup and after 3d, printing a bunch of brackets. We made that a reality, but all of the power in the world doesn’t really matter.
If you can’t get enough traction to properly use it. My wheels would just spin endlessly and i’ll never accelerate as fast as i want and that’s, because the available attractive force is roughly equivalent to the coefficient of friction times the car’s weight, plus the available downforce and that’s, where the fans come into play. These fans literally suck the car to the ground through the under tray. The tray is 8.25 by 11 inches, which is about 90.75 square inches of area, and the fans themselves can drop the pressure by about six inches of water, which is roughly equal to 0.21 psi. And if we take the 90.75 square inches times the 0.21 psi. We get 19 pounds of downforce that is 2.4 times the weight of the car, which in racing terms is massive. I also played around with different traction compounds to make sure that my coefficient of friction was as high as possible, and i should also point out that you can only take advantage of the weight over the driven wheels in terms of traction force, which is why i Switched from my original two wheel, drive fan car to this new four wheel, drive chassis. That gives me a lot more available, attractive force. If i assume my friction, coefficient is only 0.8. That means we have a tractive force of 0.8 times 8 plus 19 pounds which equals 21.6 pounds. That should give us enough traction to provide just over two and a half g’s and let’s, see if we’re, even close to being correct.
We’Ll start out with a warm up run that doesn’t use any fans and then we’ll go straight to some hard launches Music. Oh, it turns out, i destroyed the slipper clutch right off the bat, which is ironically only there to prevent me from damaging the driveline with too much torque, but in this case it literally sheared the metal lugs off the slipper, so it couldn’t really engage at all. I did have a strong idea that this may break, though so i had a slipper clutch, eliminator handy and we went ahead and installed that so we could get back to running, and at this point since i already had it apart and knew, i was just going To break the next weakest length, i also went ahead and rebuilt the differentials with much stronger components and replaced the rear axles with some heavy duty steel axles, in hopes that i wouldn’t break those as well and finally, despite leaf blowing the track that’s right, i went Through the effort to leaf blow the track, i shattered the lens on my gopro. So i also designed and 3d printed some nozzle extensions on the fans to try and redirect some of the rocks that the fans throw out away from my camera. And you can see it kind of worked in the left here. I have no nozzle extension and on the right i have the nozzle extension and you can see how much bigger the cloud is on the left fan than it is on the right and now that we’ve got it rebuilt let’s go see what breaks next Music Music! This test is exactly what i’d hoped to see.
I can consistently exceed two g’s and in my best run, i hit three g’s of acceleration. I eventually destroyed the spur gear, which meant i was going to call it a day and while reviewing the data, i noticed that i really didn’t consistently hit 60 miles an hour, which meant i needed to re gear, to give myself a little bit more top end. After a quick swap, we were back out of the track. This time we went to a different track which really wasn’t too smooth, but i still saw some very promising times Music. However, i noticed that the car kind of stutters off the line, which was reflected in both the accelerometer and gps data. My suspicion was that it is something known as the punch setting which controls how hard the car launches. So we cranked that up and sent it. Of course, this means i snapped the front drive shaft, but something wonderful happened now remember: we’re trying to beat a 1.9 second 0 60 of the tesla, and i saw that my fastest run on this time was just over two seconds to 58 miles an hour. We are incredibly close, but i also noticed that i still don’t have the peak power quite where i want it so consistently hitting 60 miles. An hour is going to be a little bit of a challenge with this much downforce. To get back to running, i had to make a trip to the traxxas store for some extreme heavy duty front drive shafts.
That is seriously what traxxas caused them. We swapped those out, and it seemed like a good time to start playing with motor timing settings to get a harder launch and just really dominate the tesla. And because my next runs were in a much larger area. I could run some cornering tests and, in this example, i’m showing that i can consistently hit two g’s while cornering and even three g’s intermittently. Imagine the advantage. This would give you on a race track where you can literally hit like two or three g’s. Even in a low speed turn, when i run with the fans off, you can see that i’m lucky to maintain just one g but let’s get back to beating tesla Music once again, i’m stuttering off the line. But it looks like the rest of the run is actually going really good Music and after reviewing the data, we have hit a 0 to 60 time of 1.825 seconds. That’S right, we officially beat the tesla and now is a good time to talk about the tesla time. As a matter of fact, because you see what tesla does, is they subtract a one foot roll out just like motor trend and a lot of other auto review magazines? That means they don’t actually start the clock until the car has already moved a foot which, in a lot of cases, measures something like 5 to 60 miles per hour instead of 0 to 60.. So if we go ahead and adjust our data for a 1 foot roll out, i get a 1.
64 seconds versus the 1.9 seconds of the tesla, which is even more impressive, seriously. Watch how fast this car leaves us behind Music Applause that’s still not enough. For me, though, because i feel like if i can just fix the stuttering, this car has so much more in it. My hypothesis now is that it’s, the side skirts dragging on the ground, creating a ton of friction, making it hard for the motor to kick off. Initially so i’ve added these bearings to the skirts and hopes they’ll reduce friction if the skirt does hit the ground, so let’s go test Music and, of course, that didn’t do it all what i hoped, because the bearings over the uneven concrete make the car really unstable Over even the smallest seams or bumps so instead of trying to get a good time i’m going to show you what it looks like when we run with the fans off, you can see, there is a ton of wheel spin at launch and if we look at The graphs we barely ever exceed one g of acceleration, which means we would never hit the zero to 60 time we’re going for with the fans off. For my final day of testing, we are going to change motor settings one last time and we’re going to re gear again to push the power band even a little bit further out, hopefully squeezing out a few more tenths of a second to get our time down.
Even more, i also had this brilliant idea to connect the fans to the throttle so that they’re activated when i go full throttle and launch instead of using a servo tester. That means i’m draining more battery than i want to well. That was bad because it turns out the fans actually can’t spool up fast enough to prevent me from doing a standing wheelie at full throttle. Luckily, the car and camera were fine, so we were able to go back to the original setup and do two more runs. Music, this time we drop to a true 1.73 second, 0 to 60, and if we subtract the rollout, we get a phenomenal 1.46 second 0 to 60.. This is half a second faster than the fastest tesla, which is massive, and i know with more testing and tuning. I can even beat this time because on other runs, i have even worse launches but much better average acceleration after you get past that first stuttering phase, i do think a sub 1.4. Second. Zero to 60 is very realistic with this car, but i’ll save that for another day. If we dive a little bit deeper into the design details of this car, we see that the fan and electronics architecture is actually pretty much identical. To my prior example, where i had 250 millimeter edf fans driven by their own independent escs and those were controlled by a servo tester, so it was as simple as turning a knob to give myself the specific downforce setting.
I wanted for the entirety of the run. However, i did move the fans to the middle of the car instead of the rear for two key reasons: the first is weight distribution. This allows me to really center the weight of the car and also reduces my rotational inertia. The second reason was to keep the frontal area as low as possible, because i wanted to reduce, drag to help my 0 60 time as much as possible, and because of that i do wish. I would have ran a 0 to 60 without the gopro, because it would have just given me a little bit more and hopefully shaved off a 10th or so we’ll do that in the future. The chassis itself was a slash. 4 wheel, drive chassis versus the previous two wheel, drive chassis for the obvious reason of having all wheels driven, meaning we take advantage of all of the tractive force. It also is a mid motor chassis, which means i have further improved my weight distribution over the legacy. Two wheel drive chassis, which has the motor in the rear. All the metal parts were plasma cut again, just like the last build and i reduced the under tray area actually to limit the downforce to what i could reasonably use, because i do have enough downforce in this setup to not be traction limited at all i’m. Actually, power and torque limited by the electric motor battery esc combo. I have so really to get more improvement.
I would probably have to either change the motor or maybe even improve the c rating of the battery. One of those two things at a minimum would be required to really get my time down that much further and to talk about why the front wing looks so incredibly stupid. It’S only there to protect the front shocks and a arms, so it has nothing to do with downforce it’s, just a protective thing, because i am really good at crashing. Rc cars also builds like this can be a huge challenge.