I have decided to step it up a notch a build a top notch modular harness for my newly aquired SM2. I'm looking for any links info tips etc that will get me on the right track. I need it to go through the fire wall via a big panel mount connector and I want to install connectors which will allow me to disconnect subharnesses from my ignition, sensors etc.

I already found a couple sources for flame retardant sleeves, heatshrink etc but I'd like to find a larger selection of high quality connectors and wire wraps, clips etc.

I am not going for the tape/split loom look. Also trying to keep this within a reasonable budget.

I used to build. repair custom harnesses for jets and helos when I was in the Marines. If I only still had access to all of those crimpers and connectors.....

-Rob

 

You can get very nice mil-spec cannon plugs from your local electronics store (not Radio Shack, lol). The wire and connectors are usually a bit more difficult to source.

Here are some links that may help.
http://www.raychem.com/
http://www.1sourcecomponents.com/
http://www.radix-wire.com/

If all else fails, you can order top-quality components from Motec or Magneti-Marelli.
http://www.motec.com/catalog.htm
http://www.servoconnectors.co.uk/aut.../Whats-New.htm

I hope you consider $300-600 reasonable.

 

Rob,

For heatsink use the raychem dr-25
for wire i like to use mil-spec m22579 tefzol coated.
I use 22ga. and 12 ga.

for connectors you can use the autosport but they are bit pricey and you'll also need different crimper(not standard milspec crimper) with special turret.

you can save a bit using the mil-spec connectors.

Amp also makes very inexpensive bulkhead connectors that you could also use to go thru the firewall.

i would definitely NOT order this from motec unless you really want to pay thru the nose.

Goto www.p-r-s.com they have everything and are pretty reasonable with prices.

 

This is going to be somewhat of a step-by-step writeup thread...

I am going to use the Autronic wire harness and modify it to fit my needs, so it will not be completely from scratch. I want to get this layed out one step at a time.


step one 1) I will cut the Autronic harness at approx 1ft behind the connectors and teminate it to a milspec cannon plug (free hanging). I will need to take the long cut portion and terminate it with the mating connector (panel mount) which will mount in the firewall. This firewall junction will: allow me to remove my ECU in seconds, allow me to cleanly plug in any future ECU (SM3?) with only needing to build a 1 ft jumper, creat a testing point for electrical problems, and will provide an airtight and secure seal between the engine bay and the passenger compartment.
What guage pin is recommended for the data wires, and will I need to use a heavier guage on the power wires (12V, Ground)?
I would assume that yo do because the power wires are slightly heavier in guage. If this is the case then I may need to purchase a cannon plug set allowing power (thicker) and data pins (smaller) instead of a plain data pin type connector. It will need to be able to hold at least 30 data pins and 2 power pins. (counted 32 wires out of SM2)

what amperage would you set up for on data (5 amps?), and then power?

 

Enzo, Do you think the OEM wires will suffice or does the mil-spec m22579 tefzol coated really make a discernable difference? I would expect Autronic to use some pretty good wire to begin with...

new wire (aka build harness from scratch) = need new SM2 connectors. Available? if so how much will they run with pins and what will I need to crimp them with?



-Rob

 

I can get you new connectors with pins. If you look closely there the same as turbo 2 plugs.

there made by amp.

The milspec wire is your choice. The originial wire is good stuff. The milspec is much lighter and smaller and very resistant to heat and chemicals. These benefits come with a price though.

SM3 was already made years ago and only a handful were made. You'll never see one.

You will however see the New SM4 at SEMA. They won't be available to dealers until a later date. There's a lot of new features not many people will know how to use yet. So it's going to take us some time to get to know the system first. I would expect by the end of this year we should have them.

Putting a milspec connector thru your firewall is a very good idea. This way you could always upgrade to other setups and not need to re wire. Just make short adapter harness.

Rule of thumb keep the power, & ignition, seperate from the rest of the wires. So you should use 3 connectors thru the firewall.

 

you wouldn't happen to have part numbers for the MILSPEC connectors would you? ;o)

or there are these plastic panel mounts; don't know how they'll hold up in the heat though... http://www.action-electronics.com/ampcpc.htm

how much should I expect to pay for a set of wires? and what gauge should I purchase for the power and ignition?

 

nevermind, 12guage (just reread it)

I'm doing some material scavaging will update on what I find.

 

for the wire I am going to go with 16878/4 teflon coated silver plated. Rated at 600 volts RMS and 200 degrees C (392 degrees F). Pretty much the best wire available for this application. I found some 30/7 for about 50 dollars for 500ft which is an awesome price considering that it can go for $2/ft +. Still looking for some nice 12g

I'm still deciding on the connectors. I've thought about going with the plastic Amp panel mounts. I have spent more hours than I care to mention repairing cables with stressed wires (do to the heavy weight and stiffness of the harness it's self tugging at the "strain relief"), and pushed pins. In my 5 yrs of doing this I never saw one plastic plug with a pushed pin and now nost modern cables are made with lightweight full loom or mesh wrap (instead of heavy heat shrink) to reduce weight. Now I think this application is a bit different since the cable will rarely be unplugged but I am going to try to keep things as light and as idiot-proof as possible.

I know this seems kinda menial to go into such description about a cable but I hope that this thread will serve as a guide for someone needing to build a harness some day so I'll try to write every step.

 

The pins for those connectors above only come in 16-22g so I'm going to have to find some different power and ignition connectors or just go with 16g wire.

I need clarification. Should I make the ignition runs heavier than 22g?

Can't wait to read about the SM4. I've heard that it is actually going to be around the same price range as the SM2 and be considerably advanced. I'm sure that it will be well made and virtually problem free if Autronic is as fervent about quality as they seem to be.

Plug ;o)

Rob

 

Great thread, keep the info and tips coming as I'm very **** about wiring looms/harnesses myself and would like to re/re much of the fragile components on the racecar.

 

Enzo if you can order me a set of the AMP T2 connectors or give me the PNs that would be great.


I've will probably go with silver plated 16g power/ign so I can stick with the plastic round AMP connectors across the firewall. I need to make sure they don't have any 12gs in the same style connector first but I have yet to find any.

We have a nice $250 digital label gun at my work that I think I'm going to borrow for this project ;o)

Checked te AMP homepage and they have a botload of sealed sensor connectors for what I want to do. still checking on the round guys.

I've got: loom, mesh, transitions, heatshrink and pretty much everything else lined up.

still have to see about tools.

will update in about a week......

here are a few more supplier links: http://www.strancoproducts.com/?thom...Multiconductor

http://www.jaguarind.com/

http://www.andersonpower.com/

http://www.servoconnectors.co.uk/aut...Heatshrink.htm

http://www.tonyjames.co.uk/about_materials.htm

http://www.steinair.com/connectors.htm

thought about using a shielded multiconductor data cable http://www.aerospacewire.com/Catalog/Plenum11.htm

 

I have all of the partnumbers for the CPC connectors ready to go but I am beginning to secong guess the idea of bulkhead connections. Maybe i would be better off if i just ran the wires through 3 seperate grommets? this would save me atleast 100 dollars and eliminate points of failure.