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[Richard]

I'm very sorry but I got a great chuckle out of your broken wire story, really very, very sorry. It struck me that the guys that built the original cars probably had similar problems in the beginning. Not sure which is worse losing a race or getting stuck somewhere far from home because your car won't start and you have no idea why.

On my car they moved the horn button from the dash to the end of the turn signal lever which also controls the high beam switch. I think this may be an anomaly, or a "feature without a benefit" as I like to call it. Now every time I try to flash someone or turn on my brights the horn goes off. Now even though my car is "finished" my list of things to fix is almost as long as my "to do" list was when I started.

Someone please tell me this is the fun part, the time where I get to enjoy my car? Don't get me wrong I love my car and it drives like no other car I've ever driven, so I guess it's time to shut up and go work oh sorry enjoy the car.

 

[Jack]

Richard, that is the fun part! Now you've been told.

 

[Richard]

Just thought I would share a picture of an original road cars dash. It may have been common practice to use the Dymo lettering on the race cars probably because things changed so much but it's just plain tacky IMHO. As you can see no Dymo lettering anywhere to be found. I'm guessing but it looks like the key fob may be in the way of getting to the horn button. I also getting a little dizzy reading the instructions for the turn signal lever.

I also love the fact they used the same fabric for the seats that was used on the 1966 Mustang.

p.s. OK I'm not saying it is but there might be Dymo lettering behind the key fob, maybe, could be, can't really tell. Anyway it may not be the horn, it may the the Fuel Pump switch, maybe.

 

[Seymour Snerd]

Just thought I would share a picture of an original road cars dash..

So it looks like each side of the lower dash was basically covered by an engraved gray plate with white letters. Is that right?

Also, the warning lights are completely unlabeled?

I think the (probable) fuel pump label is just another small engraved piece, not dymo.

 

[Richard]

I would think the lettering was silk screened but that is just a WAG.

 

[Richard]

Sorry I tried looking up WAG and didn't get what I expected so I'm not sure people will know what I ment. An x-Airforce friend of mine used it all the time. Wild Ass Guess. No clue on the warning lights. Close up it does look like silkscreen. I love the On/Off with no switch. Maybe the lights go with the gauges they're next to?

 

[Jack Houpe]

I have been involved with electronics for the past 38 years, when I got my car (roller) I started to examine the wiring and decided to rip it out and start over. I didn't tear out all of it but what ever I thought to be a problem was removed and replaced. I will say if your running a carburetor and distributor, your probably OK but if your using state of the art EFI, electric water pump, and other modern stuff your going to have problems. The fused main bus that goes to the front of the car and back to the engine compartment and then back to the fuse panel is something I thought to be darn right stupid so I changed all that before putting the engine in. I am so far very happy but still consider the wire sizes to small for some items. (blower fans, lights ect..)

Richard so you don't feel alone I had a problem with my push button switch too and I had fiberglass splinters to prove it. The lettering looks laser etched onto anodized panel.

 

[Seymour Snerd]

I The fused main bus that goes to the front of the car and back to the engine compartment and then back to the fuse panel is something I thought to be darn right stupid so I changed all that before putting the engine in.

Yes there is certainly a lot of heavy red wire running up and down the RHS. how did you lay out the bus?

(And I think you can blame all the back-and-forth on the ammeter, right? )

And yes, now that I zoom in the photos I can see they are not engraved plastic.

 

[Jack Houpe]

You hit the nail on the head Alan.

I cut all that out and put the main fuses up front and replaced the amp meter with a volt meter. In the old days measuring current flow was a means of telling you if you had a problem with your electrical components, these days our components are much better and measuring voltage gives us the ability to tell us if the alternator is working to its potential.

 

[Seymour Snerd]

I cut all that out and put the main fuses up front and replaced the amp meter with a volt meter. .

So, in short, Alternator over to Battery (~2ft) then bus from there to fuse panel (~6 ft) and that's it, right? So did you move both the 80 main fuse and the 40A fan fuse up under the dash? I was thinking you'd want to leave the 80A fuse in back to protect the long bus. ??

 

[Jack Houpe]

So, in short, Alternator over to Battery (~2ft) then bus from there to fuse panel (~6 ft) and that's it, right? So did you move both the 80 main fuse and the 40A fan fuse up under the dash? I was thinking you'd want to leave the 80A fuse in back to protect the long bus. ??

Yes I moved both fuses under the dash, actually they are attached the the panel that the key switch is attached to. I mounted my battery up in the passenger foot well then from there welding cable back to the starter, then from the starter to the alternator. The two main fuses are fed off battery kill switch which is located just under the key switch. The flow is from the front of the car to the back rather than from the back to the front.

 

[Seymour Snerd]

Some more on the starter switch supplied with my SPF GT40 P2160:

As I mentioned back in July of 2011: due to the poor wiring practices used at the factory one of the wires to my starter switch had quietly broken off behind the dash. I fixed that. The other day I went to fire up P2160 for the first time and discovered that since then the other lead had broken off.

So at this point enough was enough with that s****y switch. I researched alternatives and discovered there are many with a better terminal style than the set-screw type we have.

(But keep reading because here's a chance to raise your GT40's reliability even more, and it's cheap and easy.)

Then, I discovered something alarming: the supplied switch is way under-rated in current carrying capacity for use in my car. I have a McLeod ministarter that draws a little over 10A steady-state. There is no version of that switch that I can find rated for more than 2A. So this is another "meet the tow truck" incident in the making. Even so the same switch from Digikey costs $24:

http://www.digikey.com/scripts/DkSe...&lang=en&keywords=679-1060-ND&x=0&y=0&cur=USD

There are a lot of pushbutton switches out there with 1/4" faston terminals which is what I wanted. In particular there is the Lucas switch (SPB106) supplied for our horn buttons. That switch would be a near drop-in once you've terminated your starter wires with female faston terminals.

However, I could not find a current rating for the Lucas switch and so decided to keep looking. Also the Lucas part costs ~$30.

Here's what I ended up using, for under $5:

KFB2DNA1BBB Cherry | CH944-ND | DigiKey

Here's the spec sheet:

View attachment CHE_214683_KF_Wtrprf_Rckr_DS_D.pdf

This is a simple, plain-looking weather-proof pusbutton switch rated for 20A at 14VDC. Ir is a "snap-in" switch although it will not snap in all the way into the hole in our dashboards. I chose to push it in until is was firmly attached. Later I will carve a little on the edges of the hole to make it seat completely. It has 0.187" terminal tabs, and to fit those perffectly you can buy these:
http://www.digikey.com/scripts/DkSe...ang=en&keywords=298-10006-ND&x=9&y=10&cur=USD

I found that my already-installed high quality 1/4" female faston terminals worked fine.

You could also use a 20A Dorman 85984, but it is slightly small for the dash hole (5/8" instead of 3/4") , has screw terminals, and requires surprisingly strong pressure to activate. And it's funny-looking.

You could also keep the existing switch and install a relay to handle the extra current. I declined that option on the basis that the increased complexity reduces overall system reliability while there is a simple parts-swap as the competing solution. Besides, I have no affection for the form or function of the stock switch (it belongs on a vending machine) and really wanted a chance to "float test" it in the nearest sewer.

In any event, do something. That original switch is going to quit working someday.

(PS: with a clip-on remote starter switch P2160 fired up. Regarding the ensuing sounds, I quote Terry Hatcher in "The Implant" episode of Seinfeld: "...They are real and they are spectacular!")

 

[Rick Muck- Mark IV]

Alan,

The starter draw is not going via the switch, the switch is feeding the starter relay. If the full amperage went via the switch, the starter cables would need to feed through it. Are you saying the RELAY draw on your starter is 10 Amps?

Perhaps it may be under capacity for the relay also, but to date we have had no trouble with it that I am aware of.

 

[Seymour Snerd]

The starter draw is not going via the switch, the switch is feeding the starter relay. If the full amperage went via the switch, the starter cables would need to feed through it. Are you saying the RELAY draw on your starter is 10 Amps?

If by "starter relay" you mean the contactor and solenoid mechanism that is a part of the starter, the answer is yes, it draws 10.4A. Go measure yours and tell me what you find.

As for "we have had no trouble with it": that just means your lucky so far.

 

[Richard]

We could always add a relay to the starter relay, I think that's right. I've thought from the very beginning that I should wire up the momentary side of the key switch as a backup. Not a sexy as the push button but after all that was what it was designed for.

 

[Seymour Snerd]

I've thought from the very beginning that I should wire up the momentary side of the key switch as a backup. Not a sexy as the push button but after all that was what it was designed for.

That's yet another good alternative. The stock rotary ignition switch likely is designed to handle starter solenoid current, unlike the stock start switch which is in reality an "anti-vandalism" switch designed for use in vending machines, ATMS, etc. Here is the spec sheet View attachment AV-B.pdf

A derivitave option from that alternative is to then move the rotary ignition switch to either the hole currently occupied by the start switch, or to the one currently occupied by the horn switch. Either would be even more period correct, and would allow you to abandon the somewhat tacky-looking "center console" supplied with the car.

Then you would have an open footwell like a real GT40 and would be able to admire your passenger's ankles while underway.