How to Make Your RC Car Faster?

Last Updated on December 4, 2023 by Jaxon Mike

Radio-controlled (RC) cars provide an exciting hobby and racing experience. Pushing your RC car to go faster can increase the fun factor and give you a competitive edge on the track.

While there are many ways to make an RC car faster, some methods are simple tweaks while others require advanced modifications and fabrication. Understanding the core areas that affect speed is key to getting more speed out of your car safely and reliably.

The easiest first step is to ensure your car is properly maintained and adjusted. Cleaning, lubricating, and replacing worn parts reduces friction and resistance. Checking for binding, sloppy mesh, and unbalanced rotating parts will allow your car to run smoother.

From there, look at tires, batteries, motors, drivetrain, chassis, suspension, and aerodynamics to find ways to reduce weight, friction, and drag while increasing power.

Small changes can add up to big speed gains. Let’s look at some of the most effective modifications for making an RC car faster.

Tires

One of the easiest ways to pick up speed in an RC car is by changing the tires. Using a softer tire compound provides more grip and less rolling resistance. This allows the tires to conform to the road better and spin up to speed faster. Just be aware that extremely soft compounds will wear quickly.

Larger diameter tires also increase top speed. The greater the tire circumference, the further your car will travel with each rotation. Going too large can cause clearance issues, so consider the maximum size your vehicle can fit.

Proper inflation pressure ensures the largest possible tire contact patch without excessive bounce. Run the hardest pressures you can without losing grip.

Upgrading to quality rubber tires made specifically for RC use is recommended. Avoid cheap plastic and foam tires.

The advanced compounds in hobby-grade tires optimize grip and longevity. Consider directional tires on the rear for straight-line stability. Belted construction and stiff sidewalls also help handling at speed.

Batteries

The power source is critical for delivering the energy needed for maximum speed. Upgrading to lithium polymer (LiPo) batteries is the best option. LiPo batteries offer higher voltage per cell and lower internal resistance compared to NiMH batteries. This allows more current delivery for increased speed.

Higher voltage packs with multiple cells in series provide more power to the electronics. Common RC car voltages range from 2S (7.4V) up to 6S and above (22.2V+). Note that higher voltages require ESC and motor upgrades to handle the power.

Motors and Electronics

The motor converts battery power into rotational force that drives the wheels. Higher-performance brushless motors can provide more rpm and torque for increased speed.

Sensored brushless motors use Hall effect sensors to precisely control timing and deliver instant acceleration from a standstill.

Higher turn motors have more wire windings in the same space, creating stronger magnetic fields and increased power density.

This allows for higher rpm within the limitations of the small motor size. Be aware that extremely high-turn motors draw more current and run hotter.

The electronic speed control (ESC) sends regulated power from the battery to the motor. High-quality ESCs can handle higher voltages and current draws needed for maximum speed. Features like low resistance FETs, efficient cooling, and programmable profiles optimize electronic power transfer.

ESC programming allows customizing parameters like low voltage cut-off, timing, acceleration, braking, and top speed. Fine-tuning the ESC to match your motor and battery combo squeezes out every bit of speed.

Drivetrain

The drivetrain transfers rotational force from the motor to the wheels. Lighter components like drive shafts, differentials, gear sets, and dog bones reduce inertia and friction losses. Titanium and aluminum upgrade parts offer strength with minimal weight.

Sealed differentials prevent gear oil leakage for smoother running. Shimming the differential properly removes any backlash in the gear mesh. Hardened steel alloy gears stand up to high-power applications. Lubricating the drivetrain with low-viscosity silicone-based oils minimizes resistance.

Setting the gear mesh with precision spacing eliminates slop between the spur and pinion gears. Allow about 0.1mm of backlash without binding. High-quality adjustable motor mounts help optimize gear engagement across all terrain.

Chassis and Suspension

The chassis provides the central platform that connects all the parts of the car. Chassis constructed from graphite, carbon fiber, or 7075 aluminum offer maximum stiffness while minimizing weight. This prevents flex that can soak up power.

Adjusting suspension geometry settings like camber, caster, toe, and anti-squat properly distributes weight for optimized traction. Stiffer sway bars and spring rates keep the car flatter in corners to maintain speed.

Lowering ride height reduces the center of gravity and aerodynamic drag. Dropping down too far risks bottoming out over bumps and jumps. Quality shocks like aluminum bodies with titanium shafts and low friction seals maximize suspension response.

Aerodynamics

At higher speeds, aerodynamic drag has a major impact on performance. Smoothing out the body shell and sealing gaps around edges, wheels, and openings improves airflow. Wind tunnel testing can precisely optimize aerodynamics.

Adding a front splitter and rear wing produces downforce for extra traction while reducing turbulence underneath the car. Just be wary of crosswinds on very high wings. Extended wheel skirts and underbody channels act like an inverted wing for pressed-down grip.

Maintenance

Proper cleaning and lubrication at regular intervals keep all the parts moving at peak efficiency. Compressed air and a soft brush remove dirt, debris, and dust before lubricating. Inspect all parts for wear and replace anything damaged.

Check for loose screws, disconnected wires, binding parts, leaking oils, unbalanced tires, and cracked bearings or belts. Make any needed adjustments to gears, belts, chains, ride height, camber, etc. Testing at moderate speeds checks for vibration or handling issues.

Maintenance steps allow your car to run like new, helping optimize speed run after run. It also prevents damage or failure when pushing the car to its limits.

Advanced Mods

For those seeking every last bit of speed, exotic fabrication and custom machining opens up endless possibilities. Parts milled from 7075 aluminum or laid up with autoclave-cured carbon fiber use strength-to-weight ratios close to that of F1 cars. Mimicking advanced aerodynamics found in top-level racing can help cheat the wind.

Extreme gearing, multi-speed transmissions, and masterful electronic tuning extract insane wheel speed from elite power systems.

Combining the highest-end components with expert craftsmanship yields RC cars faster than anything off the shelf. Of course, the costs quickly skyrocket into the thousands and tens of thousands of dollars range.

FAQs

What is the easiest first upgrade for more speed?

Switching to high-quality hobby-grade tires makes a dramatic difference. The specially formulated rubber compounds provide way more grip and reduced rolling resistance.

What gearing gives the most top speed?

Generally, going up 1-2 teeth on the pinion gear while keeping the spur gear the same increases straight-line speed. Too much gearing risks overheating the motor and drivetrain.

How much maintenance does a high-performance RC car need?

Expect to clean, inspect, lubricate, and replace worn parts every 5-10 runs. High speeds put more stress on components, necessitating diligent maintenance.

Is it worth switching my NiMH battery to LiPo?

Absolutely. The higher voltage and current output from lithium batteries give a huge boost in speed and acceleration. Just make sure your ESC can handle the power.

What is a good upgrade for the transmission?

Look for lightweight dog bones, sealed ball bearings, and one-way differentials. Shimming gears and lubricating with silicone oil also smooth operation. Titanium and aluminum parts trim weight.

Conclusion

With some basic upgrades and tuning, significant speed gains are possible on most hobby-grade RC cars. Focus on areas like quality tires, batteries, electronics, drivetrain, chassis, and aerodynamics for the best results.

Taking the time to properly maintain your vehicle ensures peak performance. For those seeking uncompromising speed, custom fabrication, and machining can push RC cars to the absolute limit.

The higher capacity (mAh) LiPo packs store more overall energy for longer high-speed runs. Capacity needs to balance run time and weight. Larger packs get heavy, putting more strain on the drivetrain. High discharge (C) rated packs maximize current flow for acceleration.

Proper charging and maintenance ensure batteries perform at their peak. Never discharge LiPos fully, store at around 50% charge, and avoid damage. Consider a voltage cut-off alarm to prevent over-discharge.