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I have been reading up on the Rusterl and have taken note has it really seems to be a platform people use to go fast in a straight line.

I was looking at the RCCA issue here : http://www.rccaraction-digital.com/rccaraction/february_2014?pg=68#pg68

with a truck shootout and with a 2C and 3C LIPO, the Rustler is a good 10 mph faster than the next truck.

What make it so freaking fast next to other brushless trucks? Is there something special about their brushless system. It is only rated at 3500 kv but some of the others are as high as 4600 kv.

I bet I could answer that question, if I knew the test cars' transmission ratio, tire height and spur/pinion size--assuming the motor, ESC & battery used in testing was constant. You gotta compare apples to apples--not oranges. If they don't test the cars with the exact same electronics, the test isn't really valid or accurate.

Okay, as I suspected, you have to be careful when reading tests like this, because few people follow proper scientific method when conducting these experiments. They don't limit the variables when comparing results, so the test is invalidated. They're not comparing apples to apples.

The electronics in those test cars are all different. The Traxxas ESC is 320A with 200A continuous; the next-most comparable car in that test is the HPI Firestorm, which also uses a 7-cell battery (at least THAT is constant between those two cars), and that car has only a 100A ESC. The Leopard V2 is a 60A ESC. In other words, the differences between the test cars is not so much the cars' drivetrains as much as it is the very different electronics used. If all the cars ran the same motor, ESC and battery, then and only then would you be doing a fair comparison of the test cars' drivetrains.

The gearing (transmission ratio, spur:pinion ratio) and tire heights all play a big role in top speed; knowing those specs for each car would be a lot more useful than knowing servo torque, battery capacity, toe-in & camber adjustments, etc...which are mostly useless trivia in the calculation of top speed.

They all said that they were running 2C or 3 c batteries with the posted speed.

While the rustler has an esc that can handle more amps, my understanding is the motors draw is lol that matters. What is different about the rustler 's engine that at a Lowe kv is faster than the others? Is it just overall gearing or is there something more to the engine is the rustler that is different than the others?

Unfortunately, you can't really know how the test cars compare unless you put the exact same electronics in all of them. The electronics in that test are all over the board. If you put the Traxxas' ESC & motor in each of those cars and THEN tested them, they'd probably all have within 10% of the same speed...and possibly even go faster than the Traxxas. At least in that case, you'd be better able to distinguish differences in the test cars' powertrains & gearing.

Physics and electron theory, that's what.

The Traxxas Velineon system is powerful!
I don't know if they under-rate the motor at 3500kV or what, but it runs very strong.

The Velineon motor is also large, almost 550-size. This likely gives it more torque, allowing it to pull a taller gear ratio, etc.

So yes, the test illustrates differences in the electronics packages of the various RTR models.

If your question is which RTR package has the strongest electronics package - 'Rustler' is the answer.

dldiaz wrote:The Traxxas Velineon system is powerful!
I don't know if they under-rate the motor at 3500kV or what, but it runs very strong.

The Velineon motor is also large, almost 550-size. This likely gives it more torque, allowing it to pull a taller gear ratio, etc.

So yes, the test illustrates differences in the electronics packages of the various RTR models.

If your question is which RTR package has the strongest electronics package - 'Rustler' is the answer.

Makes sense, thanks for the info.

Coelacanth wrote:I bet I could answer that question, if I knew the test cars' transmission ratio, tire height and spur/pinion size--assuming the motor, ESC & battery used in testing was constant. You gotta compare apples to apples--not oranges. If they don't test the cars with the exact same electronics, the test isn't really valid or accurate.

How is the test not valid or accurate? They're comparing RTR kits, not rollers. With that being said, as long as the vehicles are running the same battery and in the same conditions, the test is completely accurate. If they were testing these RTR's with the same electronics, then the test wouldn't be accurate at all because at least two of those trucks would have been modified from their original form with electronics from another vehicle.

Good point. If testing rollers, then yes... All electronics need to be the same. If testing rtr, they are tested as they come out of the box

When they test a Camaro against a Mustang, they don't let the Camaro have an aftermarket supercharger to allow it to keep up ( )

gomachv wrote:
When they test a Camaro against a Mustang, they don't let the Camaro have an aftermarket supercharger to allow it to keep up ( )

Oh snap!!!

harry697 wrote:

Coelacanth wrote:I bet I could answer that question, if I knew the test cars' transmission ratio, tire height and spur/pinion size--assuming the motor, ESC & battery used in testing was constant. You gotta compare apples to apples--not oranges. If they don't test the cars with the exact same electronics, the test isn't really valid or accurate.

How is the test not valid or accurate? They're comparing RTR kits, not rollers. With that being said, as long as the vehicles are running the same battery and in the same conditions, the test is completely accurate. If they were testing these RTR's with the same electronics, then the test wouldn't be accurate at all because at least two of those trucks would have been modified from their original form with electronics from another vehicle.

The O.P. was asking why the Rustler was so fast. The answer is no mystery; it has a much more powerful electronics system; the comparison between that and the other cars can hardly be considered a fair comparison.

Marc I think you nailed the answer to the actual question. The Rustler is nothing special, the included electronics are.

harry697 wrote:

gomachv wrote:
When they test a Camaro against a Mustang, they don't let the Camaro have an aftermarket supercharger to allow it to keep up ( )

Oh snap!!!

really suprised it only went once...OK, twice...

But the trick is... take ANY of these trucks in kit form, drop in a 7000kv $39 trackstar mill and a $50 trackstar speedo, gear it to the moon and you will blow the pants off any traxxas RTR vehicle (or any other RTR for that matter).

What also helps in the traxxas-loving bias RCCA has is the economic/people ties between both entities. RCCA has long been traxxas biggest advertiser...

Net - Why not a Rustler, but without the blinders, please.

Paul