Kudos to you, Mikesride. Speaking from experience, this is a fantastic way to spend time with your son and to begin a lifetime of shared interests. I did the same with my youngest son, at about the same age. We raced indoor carpet in the winter and outdoor parking lot in the summer (all on-road) for six or seven years and had a ball. The competition, car maintenance, along with frustrations and victories associated with both really got us talking to one another and communicating on a deeper level than we ever had. For my oldest son, we accomplished this through the outdoors - hunting, fishing, backpacking, etc. My younger son never really took to any of that, and I struggled for a way to make the same connection. R/C cars were it.
Here are our outdoor race cars, a pair of Associated Nitro TC3's. He ran an O.S. .12, ROAR legal motor. I adapted mine to an O.S. .26 four cycle, the sound of which was just awesome against all of the two strokes.
Once he reached driving age, the mold was well and truly cast. His next "toy car" project was a '68 912 roller (blown motor) he bought when he was 15. We spent the next couple of years fixing it up. Then, in his senior year in high school, we finished it up by converting it to a 911 with a 2.4 MFI motor I had laying around. Now, with him 22 years old, we are as close as ever. I attribute our relationship in a large part to those first couple of R/C cars that got us spending quality time together.
Oh, here is his latest "toy car":
