With some Power Functions elements and a few extra pieces, it's pretty easy to turn the Rally Car into an RC car.
Here's a quick demo video of my design in action.
And here are the instructions I made for it.
Required extra pieces
First you are going to need some extra pieces:
1x - Servo Motor
1x - IR Receiver
1x - Battery Box
1x - L-...
Unfortunately, this is common to several colors in the LEGO color pallette. According to this article on Eurobricks.com, The LEGO Group (TLG) made a change in the early 2000’s in how they make their colors: they used to have premixed color granules but abandoned those in favor of a system of white granules with colored dyes added in. This new system allows ...
After a bit of research, it looks like this is a new part for 2018.
The part that it is likely replacing is the old flower petal with stud connections:
The new part has 5 petals instead of 4, and they are shorter so that they don't collide with neighboring parts at any angle. New Elementary did a writeup on the new flower parts that includes an ...
This part was introduced for licensed polybags in the Racers Ferrarri line (30195 and 30190):
It has been used that way a few other times since then, but it has also been used a few other ways in released sets.
It was used in 95012-1 BARC Speeder with Sidecar to round out the back end of the CIS speeder nicely:
And identically in 75017-1 Duel on Geonosis: