I am beggining to lay out componentry for my "carputer" in car entertainment/navigation system. I will be installing a touch screen LCD and have everything figured out except for the integration with the existing audio system.

I will be installing the LCD where the factory stereo is at, and would like to completely remove the stereo if necessary. The problem being I am not sure if the amplifier for the speakers is loated in the head unit or somewhere in line in the wiring.

I helped a friend do his RSX and we were able to wire the line outs directly into the wiring harness as the amplifier was further downstream. If this is not possible I am looking for some help figuring out where to stuff a stereo (either the factory one or an aftermarket). Also trying to find out if there is an aftermarket stereo wiring harness available yet.

Thanks

 

The stock HU is it's own amplifier, so if you want to get rid of it you'll need your own amp for the speakers.

 

What else are you planning on putting in? A Carputer (nicely integrated) is much more complex than it might sound and it worrys me that you didn't know that the amlifier would be in the stock head unit. If you've got any info about your setup, I'd be very interested. If there was a good, well thoughtout, and CLEAN install floating around, I'd be totally interested. I really hate the look of the stock deck and I'd love to have something with GPS built in... oh... in my dreams...

 

I helped several of my friends build cheap GPS units for cars (PDA based) - total cost with a PDA off eBay was around $250 (and you can use the PDA as a... PDA!)

 

Computer - Hardware
I am building a small box to be mounted in the rear of the vehicle. I am having a mounting bracket made to use the smae holes as the bazooka sub. The computer will be built in a Shuttle SS51G Chasis, mostly components I have floating around the house from the other systems I have built. Nothing fancy, but a 2.0 ghz P4 (I may underclock it as the cooling heatpipe cooling system is good but not the best) 512MB ram integrated Wireless, laptop hard drive (deals with bumps and movement better) Decent video card but nothing fancy. I will of course be replacing the power suply with an Opus 150W DC-DC converter with automatic start-up and shut-down control as well as a power filter.

Software

I will probably run Media engine (untill Aimee comes out) as the interface.
I am playing with Navigation software right now but will probably use Copilot.

LCD Interface.

I plan to use a liliput 7" touchscreen where the factory stereo is located at the moment.


I will have to decided what to do about the head unit, the only reason I was asking about the amp being built in or not was because the RSX has a seperate amp located elsewhere in the car and we were able to run line level outputs from the computer direct to the amp. ;-) believe it or not I have done this twice before.

The plan is for it to look extremely "factory" no wires or strangely mounted LCD's or anything strange like that.

 

I know about PDAs and if push comes to shove I'll probably end up doing that kind of thing, but I have a hard time beliving your $250 number. The key is nicely integrated - I've never seen a PDA GPS system that really is. Even if I can handle the fact that it won't be nicely integrated, I don't want a funny looking old PDA, and then the GPS module and software is going to break the bank. You can get a nice little Dell Axim with Bluetooth for about $300. If you look around you could probably get the GPS module (bluetooth - it's got to be hideable, right?) for just over $150, and then maybe you can get lucky and pirate the software. Not counting tax or shipping or bad luck, you're still looking at closer to $450 than $250 - what parts did you use?

 

I am just going to route the speakers to an amp in the back and run the inputs from the computer direct into the amp, this will give me the ability to upgrade in the futre without pulling any more wire. The only thing I need to find still is a wiring harness. in addition to looking factory I don't plan to permanently modify anything so I can put the factury head unit back in when I trade the car in.

I want more than GPS, other wise a PDA would work nicely especially as I already have a HP iPaq 4150.

Anyone no where I can find a wiring harness?

 

You've obviously got this thought out a good bit - what do you think the whole setup will run you? What are you going to use for GPS? Also, why all the power? It sounds like you're kinda overkilling things. For example, why get a good video card if all you're going to be doing is running a 7" screen off it? Are you going to run more than 800*600 resolution? I doubt you could see anything if you did, and if not, it seems like something good just translates to hot and power hungry. I'd go for something quiet and cool.

It would be nice if there was a really custom system that would fit into some cutout that is not going to be in use - I'm planning on getting the sub so that won't work... maybe I'll just have to live with what I've got. I wish someone would integrate all this crap into a double DIN box (or at least most of it) so we could plug the factory hole up with the computer - how's that for an idea?

 

I thought about the double DIN thing, but I have most of the Shuttle Hardware already and doing a double din thing would take more fabrication skills than I have. But I think it would be possible with a VIA Eden board or something.

As far as the power, I am a gamer at heart and need a little bit of gaming ability from time to time. I am not thinking about putting a beast in there or anything, but maybe a Geforce4MX which has a passive heatsink, so less worry about fans and what not. The hardware is what I need to be able to decode Divx Movies as they do take some computational power.

Since I have most of the components I figure my out of pocket expense to be $500-600 including the screen, amplifier, dc-dc power converter and all necessary wiring. (And probably 30+ Man hours of labor)

If you don't have a computer laying around, add another $400-500

 

Yeah... I have a lot of parts laying around but not the right parts and I don't have any sort of mini-computer setup. I just wish someone was fabbing a standard double DIN enclosure with an LCD screen mounted to the front of it or something. They wouldn't need to build out all the guts, but it sure would be nice to not have to figure out how to make the thing out of metal myself.... well... I'll probably just wait to experiment on this car - it's not like my old car where I was game for anything. Please please let us know everything you end up doing. Documentation will convince plenty of poeple to follow your lead.

 

When I went to buy my scion the dealer I bought from orders them without head units in them so when you say I want this stereo or that stereo they just pop it in. I said all that to say, there is a good amount of room back there. I am not going to take mine out right now but it might be worth some one doing some measuring, you might be able to make a unit that could slide right in there like you are talking about without doing a lot of work. I may look into that a little bit more.

If anyone has those measurements let me know and I will talk to my fabricator about making a prototype to play around with, maybe I can gut my shuttle and fit it back there but it seems a little to narrow.

Keep talking, you are stirring thoughts in my brain. Where would you put an amp? under a seat? I like the idea of not eating trunk space and not having a computer sitting exposed in my trunk area.

 

Here's how I see it - especially because of the cover (which would be nice if you had something in there), you want a double DIN LCD - not something bigger, not something that slides out. Behind that you just build the biggest box you can fit. I bet that this box could be a good bit deeper than the stock box - there is usually some extra room in there taken up by just some wires running this way and that. My problem would really be that beginning fabrication. After that I would look to get a box that will take a FlexATX mobo if not smaller. The boards Shuttle uses in all their mini computers have network, graphics (some), sound, USB, Firewire (some), and possibly some other stuff built in, so you really won't need much in the way of expansion there. Add in 802.11 either via USB or PCI (might be a squeeze, but if you can get full height PCI in there that would RULE! and you've got a computer. No extra crap, and you could drag a laptop into the car to interface with it, either by plugging into an ethernet or USB port or via ad-hoc wireless. If you're lucky and your access point is set up right, you might even be able to park outside the house and connect to it. If you could fabricate the metal box for about $100, (without the screen or anything inside it) I'd be totally interested.

 

I was planning on doing this myself... and this is just an opinion, I think under the floor mat... in the foam area is a perfect spot for the PC itself... youd prob need to cut a small hole and put a small maybe 80mm fan to blow some air around, but thats about it.

 

I think that is what a lot of people are thinking, but there are two obstacles, neither of which is something you can't get around. Like you said, ventilation down there is going to totally suck. But the other thing is that if you put everything back there, you're running a lot of wires, and then you're leaving a big hole behind the LCD you put in. I REALLY like the elegance of having a computer up front because not only do you not have to run the wires much anywhere, but you're taking advantage of a spot purpose-made to house something like this, with decent airflow as well as good access to all the wires you're going to want. I think the trunk gives you more space to work with, but I'd rather not if I can help it.

 

i still would think PDA is going to be a better solution. one thing,
are
you going to wait for the computer to boot up everytime you start your
car? I would think embeded systems(PDA, HandHeld, anything you don't
need to wait for booting up) would suit automotive application. i would
think it's more rational to put a PS2 in a car than a PC, since you are
not going to get away by only touchscreen, you still need a mouse and
keyboard which will be a mess to have those in the car. also you get to
think about the heat and cold inside the car in summer and winter.
normal PC is not to design to run under those envirement

PDA can do everything you may want to do in your car except playing
DVD. since you have an iPAQ already, why not just buy a BT gps ,a huge
memory card and a $40 car mount?

I am cheap ___ and lazy bomb. I use a Viewsonic V35 + megallen gps 310
+ serial cable in my car. the whole set up cost me less than 400.
actually megallen gps 310 was bought 2.5 years ago when I got the HP
568, cost me $70. V35 cost me $300 a year ago. I use to play MP3 from
V35 when I was driving my old corolla. I tried to get couple of movie
running in V35, friends love to ride my car. then I got sick of running
those vedio compression things.

 

i think under seat will be a good location for main computer board since you get AC vent around your legs, that helps ventalation problems. putting computer hardward behind the dash board is no a good choice since it will get reall hot inside, temp is higher than the computer can withstand.

also, unless you are going to write your own program, or you will find it's rather difficult to operate a PC in a car. I use to drive sears home tech van around, they have a laptop on the car. i would say unless you have a huge touch screen (more than 12") a minikeyboard and track pointer right next to you, or you will be having trouble to operate the computer. i think there are also speical custom made program for pc in a car, but last time i checked them are way overprice that normal person would not like to pay for it.

remember that, pc crashes, all the time, and it's totally uncool when your friend want to watch dvd and you tell them you get to pull over on the road side to figure out what's wrong with your computer.

just my 2 cents

 

The boot thing is an issue of sorts - but there are power supplies and setups that auto-boot when you start the car and auto shut down when you turn it off. Plus you don't need to run a version of windows (big and crash-prone). Check out www.mp3car.com and stuff... there are lots of setups - you don't want a big interface that would be hard to control without a keyboard and mouse. You want something special built for a small touch screen display. It isn't impossible to do - it just isn't super easy.

 

im glad to see another carmp3.com enthusiast with a scion. i myself am planning to mod my car with a carputer but im not gonna do it yet until i see another tC with it. :oops:

 

I think everyone has the same idea - this is no... ford focus or something. This is my baby. I'm not doing anything to it until I can talk someone else into doing it first. C'mon... someone has to have more fabrication and electrical experience than I have...

 

I kind of started this discussion looking for some feed back and I am glad to be getting a lot. I am somewhat concerned about the heat issue in the dash, I was thinking about sticking a temp probe up there to see how hot it gets in there during operation. Computers can operate under higher temperatures than everone thinks. My old AMD Duron processor used to heat up to 70 C, that is like 150 F. The area has to be somewhat cool as that is where the current radio sits and though it was designed to be run in a car it is still and electronic device and equipped to handle heat.

I am having my dealer measure one of his cars on the lot that does not have a stereo installed so we know how a big a box we might have to work in. I have started laying out rough sketches.

Mp3car.com is awesome, if you want to see what can be accomplished take a look in their forum at the completed project section.

I know there are issues that come with a carputer crashing and interface, but they all have a solution and at the end of the project you have a truly awesome system. I realize this isn't for some people but that is what makes us all individuals. I am scared about "cutting into" my new baby too but I am willing to be the guinnea pig if I think I will get support from the tremendous collective brainpower of the Scion Life forum.

I have no illusions of grandeur that this thing will be installed in 2 weeks with no hiccuphs. I have a real life and Job and family to attend to. I am thinking about a 3-4 month total project time frame. That may even be a little optomistic as I will have to run everything by the finance comittee (my wife) and it must meet with her approval. I plan to spend the month of september planning everything out and begin aquiring the rest of the parts I need in October.

As far as the "cage" as I have begun to call it in talks with my fabricator, assuming my heat probing surfaces no potentially harmful issues this will probably begin construction this month.