Are you interested in maximizing the run time of your car? Sometimes speed isn’t everything. Getting the best runtime can be just as important. For that reason, I am going to explain what cars have the longest run time and what affects this.
What RC Cars Have the Longest Run Time? Electric cars typically have longer run time. RC cars have two main types electric and nitro. Nitro cars are more powerful and faster. But, for a quart of fuel, you will find that the runtime significantly less than you can get from a full battery.
However, in this article, I’m going to explain that it is not as straightforward as just to buy an electric car. There are a lot of other factors that come into play as well, let me explain now.
What factors affect your car’s run time?
As discussed earlier there are a number of different factors that can affect your cars run time. Here is a list of some of the main things:
- gear efficiency
- style of driving
- type of surface
- For electric cars, battery size
- And more
In the rest of this article, I will go deeper and explain more about how these factors affect your runtime.
What electric RC car battery will last the longest?
When it comes to choosing the best battery for run time it is a simple as choosing the battery which has the highest power rating. There are other factors that affect run time, but regardless, all things being equal, the higher the power rating the more power and longer you’ll get from running your vehicle.
The Importance of MAh
The power rating of any battery is based on “Milliamp per Hour” and this is abbreviated as “MAh”. You should see this on any RC car battery and is an industry-wide acronym. Not just for RC cars, this is used with mobile phones and other electric devices.
The higher the MAh rating of the battery is the more capacity it has. Meaning you can expect it to last longer which will improve your runtime.
How does the motor rating affect the runtime of the vehicle?
Motors are measured by their “Kv” rating. This is the constant velocity produced by a motor. This is measured by the RPM (revolutions per minute) when one volt is applied.
This rating will give you an indication of how fast a motor will rotate for a given voltage. To put this into context lets say you had a 1000Kv motor (hypothetically speaking), and it had a 20-volt battery (just to keep the maths simple), this would mean the engine is expected to rotate at 20,000 RPM, without any load, are you with me?
Motors with a higher Kv rating will produce more heat given the same battery voltage, and as a consequence will go faster. However, they will be less efficient and will reduce your run time.
Whereas a motor with a lower Kv will produce less heat, go slower, but be more efficient and consume less battery power. So if your only focus is run time, the lower Kv rating is more beneficial for you.
How does horsepower affect the runtime of your vehicle?
Horsepower is an important Factor. Each vehicle will have its maximum wattage and it should not be exceeded. In some cases, people make a mistake of trying to supply too much power to the vehicle.
Which will just end up in the vehicle overheating and being inefficient. This will directly affect the battery usage and can cut down your runtime.
This is often done by eager car racers who are trying to get as much speed out of their vehicle as humanly possible. But if runtime is important to you then you need to make sure that you do not overpower the vehicle.
How does weight affect the runtime of your vehicle?
RC cars that are heavy with gears need more torque to be able to move the heavier weight. This extra torque power required affects the battery life, which in turn affects the runtime of the vehicle.
To maximize your runtime you should aim to get a more lightweight vehicle so that you can push more and get a longer run time.
Q: How does Gearing affect the runtime of a vehicle
Gearing plays a huge part in the run time of the vehicle. Making small changes to the number of teeth of either the pinion or Spur gear (more on this later) affects the performance of your vehicle.
These subtle changes affect the performance of your vehicle and either push your vehicle more or reduce its performance. These changes have a direct effect on the run time of the vehicle.
Q: What is gearing?
As discussed earlier altering the gearing has a big effect. And is something a lot of RC car enthusiasts do to improve their performance. Effectively improving your gearing will allow you to get more speed out of the available power that your vehicle gives you.
When considering changing the gear ratio the most common way to do this is by changing the pinion gear and the spur gear.
The pinion gear is the smallest Gear which is attached to the motor and is usually made of metal. This pinion gear moves the spur gear which is the larger of the gears. This is typically made from plastic.
To make a change to the gear ratio you can simply replace the pinion gear or the spur gear or in some cases both of them at the same time.
In general, the pinion gear will have a bigger effect on your vehicle. So, if you want to notice a big difference go for the pinion gear. However, if you want a more subtle change and go for the spur gear change instead.
Q: What is the difference between LiPo & NiMH batteries?
There are some chemical differences within the battery that affect the charging of the battery. NiMH a different technology that is based on Nickel. WHeras LiPo use a Lithium-ion based technology.
Q: What are the advantages/disadvantages of NiMH batteries?
Very beginner friendly. Quite cheap in the manufacturing process. Quite a well know technology and commonly used in many homes. Disadvantages are it really has to be fully discharged before it is re-charged to get the best life from the battery if you neglect to this, you could notice a “Memory effect”. meaning they will not last as long.
Q: What are the advantages/disadvantages of LiPo batteries?
They are lighter than NiMH batteries and do not have any “memory effect” problems. They can also be built easily in different sizes. Also, they are quite easy to use, provided they are used with the correct vehicle. In general, a LiPo with the same capacity as a NiMH will provide a better and longer run time. Which is a big advantage.
Disadvantages are they are a bit more difficult to manufacture and a LiPo safe bag is required when you need to charge or store them (Click here to see how to store your RC cars correctly).