Car Computer in Mazda MX-5

Posted: 19th February, 2011 in Cars, Electronics hardware, Software
Tags: , , , , , , , ,

I have rather an obsession with data. Combine this with my deep love of cars, and you may begin to understand why I installed a computer in my car. It is a way for me to collect data whilst I drive!

The Japanese temptress

The Japanese temptress

The opportunities are endless, for example, I want to log acceleration, record videos using an on board camera, monitor gps position, develop a power curve plotter similar to this, as well as monitor fuel consumption data.

Unfortunately my car is not a CAN vehicle, infact it doesn’t even have an OBD II port. With all OBD II cars it is possible to calculate fuel consumption. Obviously some of the other requirements are already quite bespoke. So I am quite prepared to integrate my own sensors, write software etc.

This first post is really an opportunity to discuss what I did to build and install a car PC in my ’94 model year MX-5.

The spec is as follows:


  • Motherboard : Intel Desktop Board D945GCLF2 (onboard graphics and soundcard)
  • Memory : 2GB Kingston DDR2 800Mhz
  • Power supply : M2-ATX 160W
  • Hard disk drive : 30GB Kingston SSDNow V-Series SATA 2.5″
  • Wifi : Edimax EW-7711UAn
  • GPS antenna : Sanav TK-158
  • Case : Automotive spec case
  • Volume control : Hacked PS/2 mouse with volumouse
  • Touchscreen : Linitx 7″ widescreen touch
  • External HDD : Good ol’ USB stick (TBA)
  • Sound : Sony CDX headunit with aux plugging into on board sound
  • Accelerometer : Freescale MMA8450Q (Donated to me by work, perhaps not recommended if you are going to buy one)
  • Accelerometer interface : Seeeduino, (Arduino clone)


  • O/S : Windows XPwith enhanced write filter (to protect the solid state HDD from lots of writes!)
  • Front end : Riderunner
  • Skin : Elite lite
  • GPS : PC Navigator 10
  • Visual Basic 10 to write logging software.

To install a PC in my small little MX-5 was actually not too bad.  I started by removing the spare wheel from the boot.   I then looked at installing the screen in my double DIN dash.  Here are some lovely pictures of the process which was quite fun.

I had to cut into the plastic to allow me to route the sound and monitor cables to the boot, notice the silver tape on the left used to ensure there were no burrs.  Check out my handbrake, my girlfriend gave it a good varnish, the gear nob has now been done but not in this photo.

The headunit acts as my amp, setup on AUX plugging to the computer.  It is secured in place by velcro.  This means I can pull the kit out easily for ‘bench’ maintenance.  I have been able to keep RDS traffic updates as it is still plugged to my FM aerial, I also plan to run a fibre optic cable to the IR receiver.  This is a cheeky way of manipulating the headunit using my remote control 🙂

I went to B&Q and managed to get a large strip of MDF board back for the false floor in my boot.   I cut it exactly, using old wallpaper as a template for my jigsawing.  Now I can use the boot, without worrying about squashing the computer!

Ordering all the bits was done over the weekend, so imagine my excitement when it all arrived at work, I built it and took these photos:

I will put some more bits and pieces up in due course, as I said at the beginning of the post, just a taster of what was involved so far.

  1. the boy says:

    I do like our m-x5

  2. […] a while back I was designing my carputer.  Now the MX-5 is a sweet handling car, it is not particuarly fast, but it is so much fun on all […]

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