My Cobra Build Site

Despite spending a lot of time over the last couple of weekends working on vehicles distinctly NOT the roadster, looking back, I did actually get a fair amount accomplished. I had to spend time doing brakes and some other items on the hot wife’s Beetle, and spend most of Saturday last weekend working on the Suburban (new K&N, exhaust manifold gaskets, plugs, wires, tire rotation).

Dash Install and Holy Crap Bar:

With the rest of the dash wiring installed and tested, I went ahead and finished up getting the dash installed so that I could get the heater ducts finished up. Since the dash won’t actually be finished in terms of install until the body is on, this isn’t a final step, but will allow for gokarting when the time comes.

As you can see in the pics, I also finished up my Holy Crap bar. There are lots of names for this, but it’s for the passenger to hold onto, and it’s appropriately named “holy crap bar.” Since it can see a good bit of stress, it was important for me to get it very secure, yet be able to adjust it’s position for final dash and body fitting. I fabricated a mounting system to allow for that, then drilled the holes in the dash for it. The dash position is static, but the part that mounts to the secure assembly is adjustable up and down (not a lot of side to side movement anyway with the steering column in place.)

Some of this was already detailed in an earlier post, but here are some more pics. It’s attached to the 3/4″ dash hoop, and is pretty stout. I ended up having a bit more of a gap between the dash and the frame, though, so I added a couple of 1/4″ nylon spacers to make up for that so I didn’t bend the aluminum dash.

Pics:

Alarm LED:

I was able to get my alarm red led installed a couple of weekends ago, and so I thought I’d give the how-to on that as well. I wired it up, but since it’s going into the tranny tunnel cover now (just in front of the keys), I won’t do final install until that’s ready to go in. It did work very well though.

For those that might want to do a similar thing, here’s what I did.

Found the blinking LED here: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170477135292&ssPageName=STRK:MEWNX:IT

I used an extra housing I had from my del city order, but you can also buy them from del city or from parts express.

You don’t really have to, but I used a relay for this, just so I could make it easy to switch between the key ON and key OFF status.

Here’s how I wired it, using a standard 12v relay and socket (parts express too). I’m just going to give the wire colors, but you can look up the relay positions if you want.

Red – Battery – always hot
Blue – + side (red wire) of the LED
White – Ground
Black – Keyed 12v (ignition source)
Yellow – Not used

Obviously, the black wire (-) of the led is to ground.

That way, the light blinks when the key is off, but goes out when you start the motor or if the key is on.

I had read that there was some concern about the battery drain from the LED, but the draw on this one is 20mA. I left it running for a couple hours, and no drain at all was perceivable on my meter from the battery. I’m sure if you didn’t start it for months, it would have some draw, but in that case, you should have a battery tender on it anyway.

Interior Aluminum:

After a really cool mini-event of actually driving the car out of the shop, and then backing into the other bay, it was time to continue work on the interior aluminum. This is one of the last big steps in getting to go-kart status.

I was able to get the driver’s floor, passenger’s floor, and the bulkhead pieces all drilled, siliconed, and riveted in. Thank GOD for Mike’s air riveter…I can’t imagine trying to do all of those rivets by hand. I was glad that I ended up buying the double-ended 1/8″ drill bits from harbor freight, but wish they were a little longer. Every time I use my drill, I am reminded that I will NEVER buy another chuckless drill, they are worthless for small bits, and end up having to retighten the chuck all the time.

I was also able to get the rear bulkhead access hole cut out, which will allow a little pocket for “stuff” behind the seats, but also will serve as a location for some small speakers in the corners that will fire across from side to side to get some sound. I just drilled a few holes, then cleco’d the panel in place, marked there the frame pieces sat, and cut the hole. I added a 1/2″ to the measurement on the lower cut, which turned out great since the bolt heads on the 3-link retrofit kit make the trunk floor there sit up to almost that level. It was a pretty good fit. I’ll add a “wall” that will sit 10-12″ behind the opening.

One note worth mentioning. When I placed the bulkhead piece in place, I noticed that the holes for the seat belt routing didn’t line up right. I took a closer look and realized the cross bar was actually not even or straight across, so it stuck up about 1/4″ on the passenger side. I ended up “massaging” it with a dead blow rubberized hammer, and it fits great now.

I’m really enjoying the aluminum fabrication stuff, and just thinking through the problem solving aspect of the build. One issue I was having is the location where I want to mount the 10″ subwoofers. I want to use the rear cross as part of the mounting system, which meant that the floor was about 3/4″ too high. Relatively easily solution, I just need to make some “boxes” that will sit into the floor so that the subs will be able to be “submerged” slightly in the floor. After checking clearance on the 3-link banana bracket, I decided 2″ depth was a good size. I also checked and marked for floor supports to see how much room I had from front to back (bulkhead to trunk). I ended up with a box size of 5″ x 13.5″. I was able to get the first one marked and cut, but have not bent it yet. I misfigured the first time, but luckily I remembered to fix it before I cut. I had allowed for the 1″ lips for the bends on top, but forgot to allow for 2″ of drop. I believe I ended up with an 11×19.5 piece.

I wish I had gone with a bigger metal bending brake, this piece is about 1/4″ too big to fit, so I’ll have to bend it using some other methods.

Pics:

Wishy Washy:

My buddy Mike says I’m wishy-washy on color, and he’s probably right, evidenced by all the posts on this blog about color choice. I have now, however, made some actual commitment-based steps on color. I ordered some paint to do some test shooting. I have “decided” that I really like the black cars with silver stripes. I’ve always loved black, and this was actually the very first color choice, even before the Orange was a factor. I like how it looks like it actually wants to eat children. ;-> This is a backdraft car that I’m using as my sort of template. I’m going to take the hood off the Mustang donor and prep and tape it for stripes and color like I would the real car. I ordered some black and metallic silver paint and the necessary supplies.

Along those same lines, I’m planning on getting the body down off the ceiling in the next couple of weeks so I can get started on the body work. Some of the steps require some cure time, so doing it a little at a time along with other parts of the build should prove an efficient use of time.

Until next time…

It’s been an interesting couple of weeks since my last update. I’ve largely been working on the wiring still, and I continue to be too creative with it. A little addition here, another one there, and just when I think “today’s the day I’ll finish up the main wiring”, it really isn’t, and another week rolls by.

Dash – Take II

The big step back this last week was the realization that I definitely put my indicator lights too high on the dash. At first, it wasn’t an insurmountable issue, and I thought I could solve it by just notching the 3/4″ dash hoop. I was quickly reminded by a forum member that the BODY also sits in that same location. After some measurements by other forum members, I quickly discovered that my top left turn signal indicator would sit inside the dash overhang by 1/4″ or more. No good.

All in all, it turned out to be a hidden blessing. I had to remove the original vinyl (see last post) and redo it completely after redrilling new holes for the indicator lights.

When I started removing the vinyl, I quickly realized that it hadn’t adhered nearly as well as I had thought, and would have likely ended up with premature failure, bubbles, etc. Although I’m not entirely sure what caused the issue, I addressed it by simply sanding the dash surface a a lot with rough sand paper (80 grit) and cleaning it very well, plus waiting a little longer to make sure the contact cement cured better and more completely before putting the vinyl on. I was really pleased with how it came out, and I think it’ll be longer lasting. I also moved the indicators into more of a cross configuration, which I like better any way. 4 hours lost or more, but no big deal.

Pics of the new dash:

The speedometer is en route back home, all repaired from Auto Meter. Great service from those guys. I also found that the clock I had traded for had some fading on the hands. I sent it in for service, which they said would be $25. They ended up not being able to replace the hands, but because they quoted me that, they are replacing it with a brand new gauge for the $25, which saves me $50 at least on the gauge. What a deal!

More Wiring Progress:

It really does feel like I’m making some final progress on the wiring. This weekend was some work on the dash gauges, getting them pre-wired in before the dash goes in, the clutch safety switch rewire, and headlight switch wiring. The gauges are a little easier to wire before the dash goes in.

Door Switches, Accessory Lights, Headlight Switch Mod:

I did a full write up of the process for wiring the cockpit lights and door switches. I’ll include it here too:

I spent a bunch of time head scratching to get this all to work the way I wanted, and thought I’d possibly save someone else the time/trouble if they wanted to do the same thing.

This is a long, detailed write up of how I did it. I’m sure there are several other ways to do the same thing.

There is an underlying methodilogical debate with switching, whether to switch the HOT side or GND side. I’m on the HOT side of the coin, and have simply always switched this side. I think there are merits both ways, and probably the GND is actually better/safer. This procedure assumes the HOT side is switched, which did present an issue with the AA switch as you’ll see.

Purpose/Background:

I thought it would be great to have some door actuated interior lights, much like a production car, but also have manually operated lights for each foot box, and for the bulkhead area for the seat/cockpit (I’m doing a rear shelf and the light will light that up and spill in).

I have an LED under the middle front of each footbox (on Everson’s dash panel) and then the flexible strip is on the ¾” tube behind it and wires run in a hidden fashion. The headlight switch has a dome light setting (must be modified so it’s not GND driven), and then each footbox has a rocker switch to activate it. The headlight dome switch also controls the footbox lights, so I can turn on all interior lights light a production car. Another manual switch could be added for the bulkhead, but I didn’t need it.

Parts:

I bought a lot of this stuff over time, you could probably get all of the stuff from 1-2 vendors.

LED Accessory Lights

LED Flexible Light Strip

Standard Automotive Rocker Switches

Diodes

American Autowire Headlight Switch (modified)

Door Switches (push button normally ON switches)

Bosch Relay

Relay Harness (with all 5 pins – 87a)

Misc Connectors

Issues to be Addressed:

Backfeeding – this was the biggest challenge for me, and took a couple of hours of head scratching and testing to get it right. The system wants to backfeed between the 2 footbox lights, and also between the rear light and the footbox lights. The way I addressed it was by using 3 separate diodes (essentially a one-way valve for electricity) at each light so that the power will flow TO the light, but not feed the others. I put the diode on the 12v lead for each light, so it’s the last part of the system.

Headlight Switch Dome Switch – This switch is handy in that it already has a built in mechanism for controlling a dome light. However, the switch uses the GROUND circuit to do the switching, and the rest of the way that I wired the system uses the 12V side. This required me to modify that switch to use the 12v side instead. It’s possible that you could change the rest of the switches to switch the ground instead, but this wasn’t a preferred option for me since I had already wired everything else in and the headlight switch was the last item.

I had some plastic washers left from a metal shed install around, so I basically made another leg for the switch by drilling a hole in the switch bottom, and using a small metal bolt as the leg. I isolated the bolt by shrink tubing it except the screw end and head, and then put a plastic washer between it and the switch surface. I tested for continuity before I applied power to make sure it wouldn’t short.

I’m no DV/DT kind of fabricator, so keep that in mind, but it’ll work for me. It’s very solid, and I’m fairly confident the switch will wear out before I have any issues with this part of the system.

Hooking it All Up:

There are many ways to go about wiring everything, here’s how I did it.

Feed – I have a separate fuse panel that has both constant ON and keyed on power. I chose to use the constant side for the interior lights, this is how a production car would be wired. I have a 20A fuse for this feed, but probably 10A or less would be more than adequate, especially with LED’s.
Relay – To get this to work, I used a bosch type relay, which has a switched power source inside. The 87 lead is powered when the relay is OFF, and the 87a lead is powered when it’s ON. This gives you 2 separate sides for the door switch side and the manual switch side. When the doors are closed, the manual switches are fed by the 87a side of the relay. When you open the door, the lights get fed from the 87 side.
Footbox Switches – Everson’s Dash Filler Panel) makes a great foundation for switches. I have a bunch of switches, audio input, and 12v power ports. I put a switch to the side of the tranny tunnel for easy access to turn these on.
Rear Bulkhead – My LED strip was an easy decision for me since I am adding a rear shelf. This gave me a perfect hiding place for the light, so the strip and lighting is invisible behind the ¾” hoop. I ran the wires along the hoop and simply added electrical tape to hide the wires (the wires are very thin.) In a non-shelf setup, a nicer looking light would be needed, but same implementation. I ran a single power wire from the dash to the light area, and grounded right there.
Dome Switch Mechanism – Already described above, but more detail. I grabbed power from the main headlight feed coming into the switch via one of the taps that came with the kit. I added a bullet-type connector so I can easily pull out the whole switch assembly.

Caution – due to the nature of these builds, there is ALL SORTS of conductive metal where you’re working. I had a stray wire that blew out the fuse 2x before I figured out it was resting on the upper column. Use a meter to test as much as possible before hooking up the battery, and if you can, maybe layout a towel under your work space to keep this from happening.

Pictures:

Relay Diagram:

Headlight Switch- Labeled

Footbox Lights and Switches

Bulkhead Light and Footbox Lights (note, one led is out on the left side, pending replacement)

Headlight ON Warning Chime:

This probably wasn’t ultimately necessary, but it’s more along the lines of a production car, and with running a pretty small battery, it made sense to do it.

I just posted this for niceguyeddie in PM, and I thought someone else might find it useful. I’ll get some pics later, but they probably aren’t even really needed.

Both of my daily cars have automatic headlights, so I was concerned that I’d turn these on in the evening and forget them, so I figured wiring in a chime will help me remember.

I bought a $10 door bell type chime from Radio Shack, and wired it in. Works fine, and it’s annoying enough, I’ll never forget the lights. I’m going to be adding a turn signal reminder buzzer the same way, RS sells the piezo buzzer for $7 think.

Here’s what I did:

Mount…I mounted it facing down in the Everson under dash panel, but it could be moutned anywhere that you can hear it (it’s loud.) This worked well for me.

There are 3 wires on the chime, blue, black, and red. The blue and black go to ground. When the black and red are hooked up, and 12v at red, and you take the blue to ground, it chimes.

So, I wired the blue and black to ground together.

I took a bosch relay and wired it this way:

SWITCH (black on my harnesses) to the KEYED ignition circuit.
GND (white) – ground
THROUGH (87a) to the RED wire on the chime.
SWITCHED POWER (Activated side – yellow) – Cut off and capped.
12V IN (blue) – I used a tap to grab power from the dash light circuit – you could also use the tail lights or parking lights.

Basically, no power to the relay at all with just the key on…so, the relay won’t fire. When the KEY ON and headlights ON, the relay has power, and it’s fired, so power moves from the 87A side to the 87 side, and no power to chime.

Turn the key off, and the relay is not firing, but has power from the headlight switch, so the power is at 87a to the chime, and DING DING DING!

Took me a while staring at it, but it works just fine.

Video:

Holy Crap Bar:

I love that name. ;-> Basically, it’s a grab bar for the dash that the passenger can use if you get a little over zealous with the go pedal, plus for getting in and out of the car.

Since the dash is not to support the bar on it’s own, a support mechanism had to be built to support it. I used some steel angle I had around, and made it in such a way that it can be adjusted upward as the dash gets installed into the body. The bar is a marine-application grab bar, and should also help with the relatively empty space on the passenger side of the dash.

Pics:

After a month of no updates, thought I’d show some progress. I have been wiring for this whole time, and took some time for the dropped trunk mod. I’ll post that stuff later, but today, the Dash.

I’m simply ignoring the fact that my speedo is en route to AutoMeter for repairs, and pretending that i finished my dash.

So, it’s really an almost. Speedo will need to go in, and the holy crap bar as well.

Thought I’d post it up anyway.

Details:

AutoMeter Ultra-Lights (oil temp delete, add clock)
LED Indicators (amber turns, blue for high beams and tangent driving)
Push button start (button was $3 from parts express)
Standard horn button
On-Off-On turn signal turned sideways
On-Off-On for tangents
Headlight switch and knob from American Auto Wire
Matching Knob for the Choke

Ignition key and heater switch are going into the tranny tunnel.

Dash Material is Marine Black Vinyl from Joann’s (50% coupon, so cheap) no padding.

Used Weldwood Contact Cement and a cheap paint brush, worked perfectly, very little mess.

Covered up the pre-drilled dash holes (small ones) with one layer in back and 2 layers in front of aluminum tape.

Cut holes with 1/8″ extra inside for gauges, perfect tight fit.

Pics: