Thread: 1988 C4 Corvette

So here are some pictures:

Motherboard


components strung out on the desk during testing, there is a desk under there!


Stock Dash: (some people call it the atari dash because it's all digital from the 80s)


This is how much room I have to work with behind the factory radio. That back brace will have to go.


Mocking things up in cardboard:


Mockup showing power supply and case fan placement:


I'm going to have to shorten up those power supply cables:


Test fit, it's going to be cozy!


Case Fab work started, so far so good!


I have to admit, I think it looks pretty cool:


I screwed down the hard drive and cut out a notch for the power supply to poke through


So I have to create the lid still and cut holes for ventilation. The power supply will be mounted to it as will the case fan.

Now you are up to speed. Time and money permitting I should post some more progress here soon.

I received my Lilliut EBY701 monitor! I tested it to make sure it works, configured it for auto on using the directions in the FAQ, and then quickly disassembled it to see if it would actually fit in my dash and work when in pieces. So far so good! I took several pictures inside and out in case you are curious about the inner workings. Here goes:

From the factory running RideRunner:


Close up of RideRunner:


Cracked open the case:


Started taking it apart:





Measuring the heighth of the screen without the case:


Measuring width:


It still works!

As you may have noticed in one of my previous posts I had to shorten the cables on the power supply (24 pin connector). Originally I thought I'd have to cut out a section of the wires and butt splice them together. Luckily I noticed Fry's has some pins and tools for working the molex connectors. I bought some pins and a crimper and did a test on one wire. It took me what felt like forever to remove the wire from the connector. I did some searching on the internet and found a tool for about $25 for removing these tiny connectors. It looks like a very simple tool. It's basically two tiny prongs sandwiched around a small spacer that allows the prongs to be inserted along side the pin depressing the tabs that keep it from backing out. You shove the tool in, push the wire in a bit and then pull the wire out. I figured I could make my own since I had some scrap sheet metal from my case. Here's how I shortened my cable, step by step:

Step 1, cut the cable. There's no turning back now!



Step 2, strip 3/16" from the cable, repeat 24 times!
Step 3, crimp on the connectors


Step 4, get the old wires out of the connector (or buy a new connector). This is where my home made tool came into play:



Step 5, start reassembling: Stick the pins in the connector. I hope you paid attention to how they came out!

Half way there:


Finally done!


The test - fits good and works good!

I think my M4-ATX PSU is afraid of the dark! I haven't been able to come up with any rationale reasons so I'm entertaining all ideas now.

Anyway, here's what's going on. I finally got back to finishing up my case and built the lid and put ventilation holes in. I mounted the PSU on the lid upside down and turned it on with the lid still off and it worked great. Then I put the lid on and turned it on, sort of. It turned on the computer's fan and within seconds shut back off. Hmmm, maybe I forgot to hook something up. So I took the lid off and didn't see anything wrong so I tried again with the lid off. It worked perfectly. The computer booted and when I turned off the "ignition" it hibernated and then turned off the power. I'm testing on my bench using another power supply to simulate my battery. I've tried a lot of different things and if I leave the lid cracked open a bit it works, but then I close the lid completely, it doesn't. I thought maybe the mounting screws were causing a short and so I switched them out for nylong screws. Nope! still has the same problem. I tried putting electrical tape around the lid to prevent metal to metal contact between the lid and the case and tested it with my multimeter to make sure there wasn't any contact. Nope! still has the same problem. I rested the lid on top with the metal touching and it worked perfectly. It just won't work with the lid closed. I thought maybe the wires get bent a little too far with the lid closed, so I ran it with the lid open but reached in and pressed the wires down as if the lid were closed. It worked fine. I'm hoping to have an Ahah moment, but so far all I have is an oh damn moment. Any suggestions will be welcome. Here are some pictures:

Finished case from multiple angles:





Working fine with the lid open and metal touching:


Doesn't work with lid closed even with electrical tape all around:

damn you, now I may do this in my 85 once I'm done the one for my GA...

I don't see the P4 cable in there; that would mean no processor power and it would produce that quick shutdown you're experiencing (I did that myself; same board, same PSU); if I just missed it, is the P4 cable loose? Or is there a wire -- possibly in the shortened ATX cable -- that's failing contact when stressed by the bending when the lid is closed? (I don't care for crimped connections; they're flaky, and are the most likely culprit.)

That's very interesting sheet metal work, and nicely laid out. I especially like the hard drive tabs.

A couple of suggestions:

• The screws and nuts holding the fan on are dangerous: the fan is a source of vibration, and getting regular fan screws -- that cut their own threads into the plastic fan body -- eliminates the possibility of a nut loosening and falling onto the mainboard.
• Add more or bigger holes for ventilation air to move through, especially at the fan. There's no such thing as too much airflow.

Nice work!

Thanks for the ideas. I'll triple check that 4-pin connector again. I wasn't aware there were special screws. I'll look for them. You are right about the vibration. The car vibrates enough as it is since the suspension is so stiff. I don't need any nuts falling off!

Ron

What he said ^^^^

I see the yellow and black p4 cable on the first picture, but I don't see it on the last one!



But it's gone here, after your cable rebuild:



Thing is, it still works with the lid open? It shouldn't! So okay, another thing I would think would be the two fans, one stalling the other, or more likely, heat right over the RAM banks, or maybe the wires are displacing the ram slightly. Try removing the M4 from the lid and place it where it should be with the lid open. Now turn it on, see what happens.

Last thing, it's cooling issues. Maybe it's getting too hot in there, not for the processor, but for the RAM? You definitely need more holes.

You gotta keep in mind these C4's are pretty warm cars too, last year I didn't put it away til thanksgiving and was still driving with the roof off.