I found the Subaru Blueprint a long time ago on the web  – not sure who deserves the image credit. If anyone knows let me know.

Ever since we started Rally Cross racing our RC cars in our homemade backyard Rally tracks we knew that we had to race in the dark at some point. If you are following my blog you may know that I am not a big fan of buying off-the-shelve products to solve those fun engineering challenges.

The first stage in my RC car Rally Lights project was to build a simple prototype LED headlight array that would attach easily to the car. I opted to use Lego Technic pieces because 5mm LED’s fit perfectly. Plus if you drill out the pieces just a little bit you will find that they fit very nicely onto standard body mounting posts.

This LED Remote Control Car headlight array connects to the cars main battery and uses 6 White 5V LED’s. 2 Led’s are wired in series with a 100Ohm resistor for each of the three pairs. The setup is a bit on the “hot” side as far as the resistor size goes, which means the LED’s may not live as long as they could if they had a bigger resistor. I also added a simple on-off switch.

As mentioned I opted to mount the lights on top of the car so that they can be easily removed for day time racing. Another advantage of clipping the lights onto the body mounting posts is that the lights don’t vibrate and flex as much as they would be when mounted to the lexan body itself. Although, I must say that my friend running an HPI Rally car had his lights mounted into the body and the vibration was not as extreme as I expected.

If you are owning a Tamiya DF03RA Rally kit you will receive nice reflectors and masking stickers that allow your car to have very nice very nice integrated head and taillights. However, the Tamiya stock setup only allows for 2 lights and the lighting kits sold in stores tend to be more for looks then for actual racing in complete darkness. I tried keeping my lights brightness and range to scale – based on the Subaru night super stages lights that attach to the hood for the Australia and Sweden rally, however first tests show that I have to go above scale with brightness to make the RC car really usable on a tight track at night.

My next project will be to add brake lights and tail lights. If you buy a brake light kit for your RC car you will notice that the lights only come on when you are actually using the brake on your radio control, however if you are using drag break with your brushless setup or are using a brushed motor with a bit of drag you may never use the brakes – especially when driving on a nice flowing rally or rally cross track like we build. What I will do is design a circuit that will look at throttle and motor rpm’s and trigger the brake lights accordingly.

1) Traxxas Nitro Monster Truck

2) HPI RS4 Rally Car on Brushless Lipo Setup

3) Kyosho Custom Stadium Truck

4) Tamiya DF03 RA with Stock Motor

The Traxxas Monster Truck has all the power in the world – but a high center of gravity requires the truck to go around tight corners relatively slowly.

The HPI RS4 Rally shocked everyone by matching the acceleration and almost outrunning the Traxxas during a tarmac drag race. But lots of power can be tempting and all to often it proves too much of a temptation for the driver.

The Kyosho Stadium truck was a custom vehicle build by its owner from many spare parts. The from axles failed early in the race.

The Tamiya Subaru was the car with the best handling. Drag racing was no fun, but on the tight Rally track the car really was in its element and won the race.

Bottom Line: POWER IS NOTHING WITHOUT CONTROL

Here is a satellite view of the new track layout with the addition.

A designed the track based on my measurements using the Carrera Slotcar Track Planner. Unfortunately we only have the “cheap” Carrera Go track – which actually has lot of potential when you replace the stock power supply with an adjustable lab power supply, replace the throttle controller with some old-school Carrera Servo 140 controllers and hook the whole thing up to your computer for some accurate lap timing.

Here is my modified Carrera Slotcar Power-Control-Timing Setup:

Here is the Carrera Slotcar Track-Planner Render:

And here is the ready to drive slotcar rally track:

And here is the timing setup using the EasyLapCounter – the Electronics Setup above shows the hoslotstimer using a phototransistor:

Simply download Torcs, install it, unpack the backyard3.zip file and move the folder into your torcs dirt track folder.

Watch the Video of my Torcs RC Car Track here or read the blog post here.

Here are some Torcs RC car track screenshots:

It seemed like a fun idea to build a drive-able computer car racing game based on our R/C backyard track and our Subaru Tamiya Rally car. Needless to say that it does not come even close to any of today’s Xbox360 or PS3 games, but that wasn’t the point in the first place. Driving my own track on the computer while looking at the “real thing” out of the window still makes me happy :-)
With the initial experience and all the measurements taken I am really tempted to build the whole thing on XNA Express to make it playable on the 360. I am afraid they will have released 3 new models of the 360 until I figure it all out though…

We finally had some decent rain which allowed me to run the RC car in the mud, dirt and rain. However, due to the high amount of clay in our soil the whole race track turned into a gigantic slip and slide. The car had absolutely no grip what-so-ever. Even just walking on the track became an issue.

Therefore no timing exists from the race day. I did pull out my waterproof (and thankfully shockproof) Sanyo WH1 Camcorder though -  to film the car in the hopes of getting a “Rally Great Britain” type video, but thanks to the fact that the car was all over the place the video is about the Rally car crashing into the camera.

At the end of the day I managed to get water into my Novak Speed Controller which of course fried the unit. I switched to the Tamiya Stock motor until I get a replacement controller. Considering that the track is very short and narrow I wonder what the Lap time differences will be. Timing and Race Results can be found here.

The drawing for first price is random, so don’t be disappointed if your model is the best looking but didn’t win.

Click on the photolink of my Subuaru WRC in the mud to check out the Tamiya Builders Showcase.

Infomation on how to submit your model can be found on the Tamiya website.

Take a look at the RC Rally pictures of the day.

“Wheels Spinning on Tamiya’s Rally Subaru”

“Hard Landing and Dust Cloud after RC Car Jump”

“Dirt Covered RC Rally Car after Jump”

“Subaru crosses Finish-line, making the Lap Counter and Timing Laser visible”

“Start/Finish Rallycross with timing laser visible”

“RC Rally Subaru cornering on throwing some dirt around”

“Remote Control 1/10 Rally Car Drifting”