The HPI RS4 chassis has been around for awhile, but HPI’s most recent iteration of the chassis features both killer looks and great improvements. My favorite version is the newer Mustang RTR driven by none other than Vaughn Gittin Jr. This body looks killer, and has a great wheel/tire setup for drifting right out of the box. Yeah the car drifts well, but who want’s to leave things stock? For today’s 3 Upgrade Ideas Thursday, I wanted to give the RS4 Sport 3 Drift a little oomph, and make it feel like you are driving a replica of the real Mustang RTR. You know what that means, more power (and control, I guess)!
1. Castle Creations 1/10 SV3 Sidewinder ESC + 6900kV Brushless Motor
You can already see where I am going with this one. A 6900kv brushless motor is no joke and absolutely overpowers the RS4 chassis when running on 2 cell LiPo. Usually a bit too hot for reliable operation of off-road vehicles, the 6900kv sensored motor feels like it was made for 1/10 on-road applications. For drifting, this is important because you want to be able to break the tires loose no matter how slow your are traveling. This is a nice upgrade from the stock Firebolt 15T motor, eh? The Sidewinder SV3 ESC can handle sensorless brushless motors, and up to 3S LiPo power (but the 6900kv motor really should only be run on 2S). This is my go-to affordable ESC for 1/10th scale applications and works well in a variety of vehicle types. The ESC is also waterproof, so if you accidentally hit any puddles you do not have to worry about anything burning up. One great feature about this combo is the motor is in fact sensored, so if you decide to upgrade the ESC in the future to a sensored one the motor can take advantage of this. Please keep in mind with this power upgrade, you may need to change the gearing from stock to keep the motor temps happy.
2. HPI D-Box 2 Adjustable Stability Control System
Drifting with high power setups can be quite tricky, one small pull of the throttle and you will be doing donuts in no time. In order to make the power more controllable, many drifters run some sort of gyro that helps prevent the car from spinning out. The HPI D-Box is great for this, and offers many different modes so the user can have as much (or as little) compensation during their drift sessions. One great feature about these type of setups is that the user’s steering inputs are still relayed and you can change direction on the fly. What this means is if you turn left while accelerating, the car will still turn left. The benefit is that the D-Box will help your car hold this left turn, while having the back end hang out just like a real drift car. And don’t feel like this is cheating either, many competition drift rigs run some sort of compensation just like this.
3. MaxAmps Hard Case LiPo 5450 2S 7.4v Battery Pack
Last (but certainly not least), we need to upgrade the battery so that our new power setup can get the required amps/volts to take advantage of the extra power. MaxAmps offers a variety of packs that would be suitable for our goal, and I decided to stick with the tried and true 5450 mAh 7.4V hard case pack. This battery has a ridiculous 120C current rating, which is way more power than we need on the Mamba system. With that said, it is always important to have a higher spec’d battery than what the ESC can draw or you may run into puffed LiPos or severely limited power. This pack is a drop in replacement on the RS4 chassis and should give amazing run times compared to other batteries out there. With a 6900 kv motor I would imagine that run times of 20-30 minutes are more than possible, and with agreeable temperatures throughout.
Part: Hard Case LiPo 5450 2S 7.4v Battery Pack
Link To Buy: https://www.maxamps.com/hard-case-lipo-5450-2s-7-4v-battery-pack
If you follow this upgrade path, your new Mustang drifter will be an absolute overpowered monster, just like the real thing! With a proper battery and brushless system you will see nice bump in available torque to break those tires free. You will also see a nice increase in run time so you can stay outside longer and enjoying the model even more. The D-Box will help you keep the uncontrollable power “under control” and will smooth out your long sweeping drifts. HPI offers tons of hop up parts as well, so if you decide you want even more options, look no further than HPI!