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Discussion Starter #1
*Hoping to update with more pictures and details as needed later on*

Hey guys...Just posting a quick DIY that is somewhat more vehicle specific to us 3Gers. If you guys wanna get started on this project, you should head on over for www.mp3car.com for any other questons you might have. I'm going to start off with each main component and what options you might have, and you can choose what best suits you.

My current system components:

Intel D945GCLF2 Dual Core Atom
2GB DDR2 RAM
80GB Seagate 5400.3 HD
Lilliput 629GL-70NP/C/T Touchscreen Monitor
DSATX 220W Intelligent PSU
Hippo Bloat DAC
Griffin Powermate
Logitech DiNovo Mini Bluetooth Keyboard
Holux GR-213 USB GPS Receiver
Metra Double DIN Kit 95-8902
Generic USB Hubs


POWER SUPPLY

There's pretty much 3 ways to do this: Inverter to a household computer power supply, a DC-DC power supply (I have a Keypower 250W), or you can get the intelligent power supplies. I have used an inverter setup in my old Accord but ran into some noise problems and it also wasn't putting out enough power so I gave that up. In the Accord, I ended up using a Keypower DC-DC power supply: it has two inputs, just power and ground so it's hooked up just like an amp. It puts out a clean signal without any problems, but I had to run a switch to turn it on. Lastly we have intelligent power supplies like the Opus, M2-ATX, DSATX, etc...Most of these intelligent power supplies have the added benefit of low voltage protection, survives engine crank, intelligent startup and shutdown (think remote wire for amps). The DSATX, which is what I am running is both programmable and adjustable for low voltage thresholds and how long the system waits before sending shutdown signal after the remote wire goes low. I would highly recommend going this route nowadays as it is very powerful and convenient. Also, all the wires that you need to power it are right in the dash already!

Here are the wires to tap (from the OEM head unit connector):

Constant 12V: Blue/Red
Ground: Black/Blue
Accessory: Yellow/Red

COMPUTER

This part doesn't really matter too much since you can throw together some old parts you got lying around. My old system in my Accord was a spare motherboard mounted into a crappy wooden box that I fabbed. So your choice of hardware is really what dictates your system placement and mounting options. With a full size motherboard, you are obviously confined to larger spaces such as the trunk or maybe under the seats. These full size boards do offer more options at the expense of real estate. In the WRX, I was tired of having this disgusting particle board box in the trunk that was held up my L-brackets, so I attempted to make everything fit inside the dash for a nice stealth install. With this in mind, I went for a mini-ITX solution (7cm x 7cm motherboard size) since it offers a good balance of power and footprint. One thing to note is that most of these boards have on board video cards, so make sure they support the resolution you want to run! This is a big issue that I will cover in the screen section.

The other thing I recommend is to go for a laptop hard drive. Some people say it is debateable as far as longevity of desktop vs. laptop drives. However from my firsthand experience, laptop hard drives are definitely much more robust. In the Accord, I killed 2 hard drives, and they crashed often during drives (the 550lb/in spring rates in the rear for Auto-X duty certainly didn't help either). After I switched out to the Seagate drive, I had very little problems except for the occasional crash, which usually was not even caused by the drive. Also, a slower speed hard drive will also have benefits being that it can take the bumps better than say a 7200RPM drive. The latest drives from WD and Seagate all have head crash protection so maybe a 7200RPM drive will be a great performer.

SCREEN

This is probably the most important part of your system since it takes everything from the computer and displays it to you. It should be outputting a clear image, and have the functions you need, since it is the main unit you will be interacting with. There are two main screens in use: Xenarc and Lilliput. There are mixed reviews of these two screens, with a lot of bashing on the Lilliput due to a lot of problems experienced. This statement was true a few years back and still true now, but I believe a majority of the complaints about the Lilliput are because so many more people use it compared to the Xenarc. I run a Lilliput myself and it works like a charm (*knock on wood*). Either way, you cannot go wrong, just make sure you get one with touchscreen because it will make your life a LOT easier. Also, make sure you have VGA input (my brother finished his carputer a year after I did the one in my Accord and he used a cheapo screen without touchscreen and composite inputs...needless to say it looks like shit and he has a keyboard and mouse hanging out the backseat). Lilliput also has an auto-turn-on mod to power on when power is detected. The 2008 models can do this in the menu system and no longer need a hardware mod. They are also LED backlit instead of using the old CCFL lighting.

The resolution problem I alluded to in the earlier section will be described here. Simply put, most of the 7" screens that are on the market and VGA resolution have a native resolution of 800x480, and the images displayed will look best at this resolution. My old Lilliput 619 was able to lock onto this resolution without issue, but it died on me when I was fabbing the system for my WRX. My newer 629 model does not detect the native resolution of the screen regardless of video card. I tried using 2 nVidia cards and the built in Intel solution and all of them have trouble. There is a way to force the resolution using DTD calculator, which is a custom resolution/timing tool. The results I got were mixed: the screen runs "800x480" resolution but it is obviously scaled. So the image is the right size and fits on the screen properly, but it displays like it is running a non-native resolution. HOWEVER, when running the front end, everything looked pretty darn good so my worries went away.

GPS

As far as GPS units are concerned, there is a much larger selection now than there was a few years ago. You can go take a look at MP3Car yourself at the many different ones available, from serial port, to usb, to bluetooth enabled. Many people are actually using the ones that can be found on ebay, and it turns out they do the job very well. Just try to find one that is based on the SIRF-III chipset since those seem to acquire and lock onto satellites quite a bit faster. For software, I have both iGuidance and Garmin Mobile PC loaded and I like the options they offer. Other software titles include Microsoft Streets and Trips, Destinator, Street Atlas, Map Point, etc.

Interface Software

Many different software can be used to control the music player, GPS, and any other functions you might have. The programs available range from Frodoplayer, Road Runner, Media Engine, Centrafuse, and many others. These all do the same thing: they organize your programs and allow you to select what you want to do with a touch of a button (hopefully you have touchscreen). I currently run Road Runner and I am sticking with it because there are many skins out for it and it looks nice. This is also the most widely used program so there is much more support (did I mention free?). Like any of these other programs, they can make your GPS software and DVD software run embedded so you can have everything running inside one program.

OBD-2

I talked about this on the old Accord board and went into it a little bit. There are OBD-2 readers available that will allow you to read codes and see any of the parameters the ECU sees such as intake air temp. You can have a digital speedometer and RPM reading. I know some guys with Evo's were working on a boost gauge using these readers and software. Supposedly you can also clear any CEL lights with this but I haven't read about it in a while. More info can be found here on the MP3Car website.

Now for most of us, when we see OBD-2 we are thinking open source and reflashing. The carputer would be the perfect complement for the Tactrix cable so you can in car tune and reflash whenever needed. No more lugging the laptop around and plugging in different wires. You can be ready to datalog all the time, with the solution already in your dash! And of course, you're almost unlimited to the number of maps you can store on a hard drive :)

Fabrication

I chose to do an in dash mount since it is cleaner looking and easier to operate. I will now go over how to flush the screen for those of you interested. First, you take apart the screen and get the front bezel that the screen attaches to. Using this piece, you're going to try and stick it into the double din slot and note any places where the housing is too big. When you find all those areas, use a dremel tool or equivalent and shave off any areas that are obstructing the bezel. Once that is done, do a quick test fit to make sure it fits as you like, then mix up some epoxy. Apply it all around the bezel, in the cracks between the bezel and the dash piece and let dry. Once that is done, apply a layer of filler (Dynatron, Bondo, etc.) all around AND on top of the bezel and let dry. Then pull out the sand paper and start sanding...starting from a low grit...about 200 all the way to 1500 grit. You can repeat a couple times for a better base layer. After that is done, repeat to smooth out any remaining bumps/holes and do the same thing as above, sanding until it is smooth and flush. Once done, you can paint the bezel with your color of choice using light coats, and sanding with high grit sandpaper in between.

Once all this is done you can re-assemble the screen and put the OEM backing plate back on to protect the circuitry. If you are doing an in-dash system, you just need to fab some sort of mount for the motherboard (assuming mini-ITX here). I went to home depot and purchased some screws, locking washers, and nuts, with one end screwed into the double DIN mounting plates, and the other end holding up a small piece of particle board. The particle board lies flat and is used for motherboard mounting. I repeated this process for a smaller piece of wood to make the hard drive and power supply mounts.

Before you put everything in the car, make sure to test fit and make sure everything is WORKING!!! It will save you a lot of headache later on. The first step you need to do is pop out the center console. You can pry on the corner of the trim and it will eventually pop out. I removed my head unit, and tapped the appropriate wires for power, accessory, and ground (power for the DSATX). Behind the head unit you will see a metal bar running across and a bunch of wires. I had to re-route a large number of these wire bundles to get the system fit. Most of the zip ties that hold the wires were cut, and wires were run behind and under the metal bar that you see. This gave me sufficient room to mount the whole system in dash.

RADIO

I do not have this, but many people are putting HD radio tuners in their cars as well. This can be controlled through the serial port and is now integrated into many front ends. I did not want to deal with this, but I have it listed so people know that it IS an option available. Visteon is one of the companies who has a product out.

WINDOWS

I highly recommend that everyone use an nLited version of Windows XP. This minimizes the footprint and results in faster boot times. There are also many other tweaks that can be done to improve system performance and boot time that you may want to look into.

OTHER

You guys can also add a wireless network card or whatever for ease of use and also to have the WiFi capability if you need it. It is very useful in allowing you to sync songs from your home computer to your car computer, and also to do a quick check on something whenever you need it. There are endless possibilities with this so you should explore and see what other things you can add. What I am doing is using dial up networking through my phone. This lets me check gas prices, weather, and even browse the web if I wanted to. This is past the basic function of the carputer and you may want to do this after the initial implementation is ready and stable.

Other peripherals are keyboards, sound cards, etc. I added a Logitech DiNovo mini later on for additional keyboard capabilities. I also have a Griffin Powermate on the way. This is a rotary knob that can control volume, change songs, etc. and is much more convenient than pushing the next button on the screen when you are driving. My sound is routed through a USB card right now, and it will be upgraded to a Hippo Bloat for higher quality sound and to alleviate the issues that plague the X-FI. I simply run RCA cables straight to an amp that power the speakers (since I am going to stay head unit-less). Otherwise you can relocate a head unit to the glove box or something and make use of the aux input.

Wires to tap for speakers on the OEM head unit connector:

Left Front + White/Black
Left Front - Blue/Orange
Right Front + Green
Right Front - Brown/Yellow
Left Rear + Red/Black
Left Rear - White/Red
Right Rear + Red/White
Right Rear - Gray/Green


Some random roadblocks/tips that I can remember from past installs and insignificant parts you may not remember to buy:
- If using a laptop hard drive, make sure to buy an IDE to laptop drive adaptor
- Since it is a computer, it will crash once in long while...you may want a master power switch to turn things off (even with an intelligent PSU)
- On long drives at night, you may want to use a dark skin or have a switch to turn off the monitor (greatly reduces glare and ease of driving)
- If you want to use 2 GPS programs, there is a program called XPort3 that will split COM port data


If anyone has any questions, please feel free to post them or contact me. I just hope this is of use to someone and not a waste of forum space :)
 

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Great post! I'll get around to this some day.

You mentioned using a darkskin or turning off the monitor at night. Can't you adjust the brightness on the screen?

Also, I imagine an Atom powered computer doesn't use much power. Have you considered using a second car battery and letting it go into sleep mode? It would probably take a couple days to kill a car battery in sleep mode.
 

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some other things..
for power, carnetix makes really cool power regulators (and one of the only ones): http://www.carnetix.com/ Auto shut down/stand by, auto shut off with low battery, power supply for the screen, etc etc.
for gps, this one that mp3 car sells is awesome, waterproof and magnetic. i've never had any problems with it: http://store.mp3car.com/BU_353_Weather_proof_GPS_Receiver_p/gps-002.htm
scantool/elmscan makes good obd stuff, if you just want obd, no tuning. http://www.scantool.net/
for the front end, centrafuse is really good. was free, but now they charge quite a bit for it. road runner was okay when i tried it out, but i didn't like any of the skins. but it's free, so that's quite nice. those are the only two i'd go with, i've tried most others, and they're either not very good or not worth the money. in the end, i ended up using winamp and microsoft streets and trips. not the most friendly for the car, but it worked better than roadrunner and i didn't want to pay for centrafuse :-\

also, mac minis make really good carputers. they use laptop components, so they're shock/vibration resistant and you don't have to build the computer yourself (which you often do if you want to use laptop hard drives). other PCs with laptop based hardware built for the car are very expensive. if you go with the mac mini, just get an intel based one so you can boot in windows. there's not much good car-oriented software for apple's OS.
 

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any pics? ;D i'm keen to try this on my ride! getting a small form factor... maybe try an apple? :eek: :eek:
 

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I personally have a Carnetix Intelligent power supply. It is definitely the cat's meow and worth the coin.
 

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Discussion Starter #9
Why would you when you could just install Windows?
 

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chongl, you have answered so many of my questions with this post. I'm no newbie when it comes to computers, and I had most of my hardware picked out, but it was all the other things, like interface and such that I needed. Awesome post!
 

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Discussion Starter #11
Thanks! Most people who set out on this are in fact computing enthusiasts (I mean why else would you want to mess with hardware for so long?). There are, as you said, many intricacies in setting everything up, even after the hardware and OS are all installed. Even when it's said and done, there's always some new skin/way to embed/feature/program to add that keeps it fresh. :)

I'll see if I can update and add more info.
 

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Great DIY.

Is there possible to use the steering wheel controls with an computer, to change songs and volume?
I have an OEM navi unit so is there possible to use the oem GPS antenna?

Im also thinking about keeping the oem headunit since it have some controls of the key, and lights.
Than I need to put my screen fore the computer somewhere else, but I cant find anyplace fore it, where it would look good, any ideas?
 

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Discussion Starter #13
I'm sure there's a way, but I never had the steering wheel controls so I can't say for sure. Same thing with the GPS antenna, but most people just get a new one since it's not that much and it saves you the hassle.
 
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