Wiring
 

I'm cleaning up the engine-side of the harness in my car. What kind of affordable, high temp loom do I want in quantities of less than 50'? What assortment of loom diameters do I want with a long-life? What about a heat-retardant loom for the hot-side over cheap loom?

For engine-bay wiring, I've been considering getting some of this for stuff that runs near the downpipe and turbo. Available in all sorts of diameters:

http://www.ioportracing.com/Merchant...egory_Code=INS

www.wirecare.com I am making a complete custom harness for my next project with disconnects at firewall from them and all engine bay wires covered in their stuff. They have a great assortment and it is all high quality.

if i was making a harness, i'd avoid loom and go straight to big fat self-fusing silicone wrap

combination of things -

http://cableorganizer.com/thermo-flex/

variety of high temp solutions

http://cableorganizer.com/high-temperature-insulation/

What is the going rate for a shop to make a custom engine wiring harness? Nothing extravagant, just to replace the stock stuff and clean up the bay?

There is no going rate that I know of for the miata. I have contemplated making complete race wiring harnesses, but can't find all the connectors new. I really don't want to reuse old ones.

are you looking for car specific connectors? or just generic ones to use? digi-key has just about every generic connector known to man.

I used to work at a company that made the wiring harnesses for some NASCAR teams. I didn't work with them at the time, but they made good money off that....With that said, we sold harnesses which were much less complex than a vehicle harness for $60-$100+ (that was for semi-large supplies of 25-50 items per batch). I would stick to a DIY solution on this and avoid expensive pinning tools.

I was looking for all the OEM connectors. I am going to be hacking up the harness again on my next project and using generic flange plugs at the firewall, but would love to make a whole new harness with new OEM connectors. Oh well.

Am I reading that correctly? An entire wiring harness for only $100?

like I said, its much less complex and we used generic molex/hirose pins and connectors. We are talking about a simple 20-30 connector on one ended, going out to 4-6 smaller connectors all using either individual color coded wires, ribbon cables, or twisted pairs. Hirose pinners are an expensive bunch, but they worked great for most cases, but I think the Molex stuff is probably much more reasonable.

If you are building your own box and wiring, then its a great option. Hell, I could still build the harnesses now since my current job has me doing pinning on our test boards.

Ultimately, the difficult is in finding the right connectors...a source for OEM connectors would be difficult to find. Although I imagine it can't be too crazy perhaps we can find some clues on the connectors with a bit of help from google.

If everyone on the board was to agree to a specific connector type, we could make this a very cheap endeavor for years to come!

i wish i remembered where i saw it, (thinking mt.net) but someone posted a place that all types of oem connectors. and another with badass connectors for firewall etc. (aviation/ mil spec connectors)

i would love to spend a couple hundred on a nice race harness with fresh oem sensor connectors and milspec bulkhead ones. i'm sure many more would as well.

Harnesses are extremely expensive to build and very labor intensive. Ever look up the cost of automotive grade wire, let alone the cost of having the wire made with custom printed (labeled and striped) jackets? The cost of the custom jig that would be required to build each harness on? The cost of the machine needed to despool and prep the wire? The cost of the machinery needed to crimp pins on the wire? And each type of pin takes its own unique applicator, generally at the cost of $2k each. Then there is a lot of labor involved to build the harness, keep up with inventory and maintain the machinery.

"A couple hundred" isn't going to come close, especially if you're asking for milspec bulkhead connectors. A milspec builkhead connector alone can easily be over $100, and you may need more than one.

I see a lot of shops charging in the range of $1k for custom harnesses, generally that's only if you supply all connectors as pigtails. That could include a bulkhead connector, but likely not milspec. Figure 8 hours @ $125/hr shop rate, and that sounds about right. Materials extra.

If done in large batches, the only way I could see drop in harnesses with pinned connectors being a wortwhile venture is if they would sell well in the $700-$1000 range depending on complexity and popularity. Ballpark range, I didn't crunch any real numbers, but I don't think I'm far off. I googled a little bit and saw some companies were offering custom drop in LS1 harnesses for $1000-1200 or so, and it looked like they were getting built as one-offs instead of bulk production. So I think I'm in the right range.

You are completely going overboard. We aren't setting up a wiring harness manufacturing center. You do not need a jig, nor do you need a wire cutting machine for this shit. Pins were all done by hand where I worked. You had your hand held pinner for good company and the wire cutters for stripping haha. our labels were printed and placed on the connectors by hand... It all followed a data sheet. Not sure why you need milspec bulkhead connectors, but perhaps my application limits don't stretch as far as yours?

Either way, you are overthinking this way too much. Automotive grade wire has higher heat insulation, but its not much more special and its not hard to get and its not that expensive either.

I think a couple of hundred is a very good point, if the tools are available and not being factored in. This was not meant to be a big deal, just a suggestion that the forum could pool resources, but no worries. I am not sure we are looking for the same thing.

Edit:
Sorry hustler, /offtopic.

I don't think milspec connectors are needed, but they were called out earlier in this thread. I think they add unnecessary cost. I do however like the idea of a bulkhead connector for serious race applications. THIS is the connector we use. Most cars would take 2 connectors, and we also offer an aluminum plate that ties a pair of the connectors together nicely. I'll also say that most applications do not need bulkhead connectors, only those where you may need to do a quick engine swap during competition. For your standard install, way overkill unless you just have to be the most baller of the ballers at the ball.

It's foolish to not use automotive grade wiring. Yes, it is more special. It has a higher temp rating so the jacket does not melt when used in autosport conditions. It's also more chemical resistant so standard automtoive chemical splash does not eat it away. Lastly, it is more fire proof, so if your engine catches fire, the fire can not spread to the cockpit via the wiring harness. The jacket on a cheap wire will burn. This is also one reason why you use in wall rated wiring in your house. Perhaps you don't think that's special, but I'd imagine you'd be fairly alone in that thought.

If you use paper tags, the tags fall off, and then it's hard to trace wires in an emergency. Nothing ever fails when convienent. You're likely to have to trace down a wiring fault to prevent being stranded, or to get back into an enduro. Paper tags can even fall off during installation, making it more diffuclt than necessary. If you're cutting by hand and paper tagging, then I doubt that you're doing much to color code the harness. Again, makes trouble shooting much harder. I'd build a harness where every wire has a unique color code and printed label on the jacket. That way the tag will never fall off, and it will always be dead simple to trace a wire from end to end. It also means having wire custom manufactured, and it gets pricey.

It's less expensive to cut and strip wires by hand only for the short term, or when you're working with only one or two wires. It's also inconsistent compared to machine cuts. The machine gets lengths perfect every time so all wires are exactly the lenght requested. All strips are exactly what you need for that pin. Everything becomes higher quality. It's also faster, as after you do the initial set up for the run, you blaze through it. Same with the pin crimping. The machine delivers perfect crimps every time. It's much faster and much more consistent. You'll never have a 'good enough' crimp come loose on you, which absolutely happens in the high vibration autosport environment. Sure, you can make a perfect crimp by hand, but it's a lot harder and more time consuming. The machine hits the crimp every single time, no exceptions, always perfect.

Also, going back to consistency issues, how could you *not* build an aftermarket engine harness and not jig it? Especially when cutting by hand.

If you didn't realize, we sell thousands of generic flying lead engine harnesses yearly. I do kind of have a clue what I'm talking about. There's a difference between 'overboard' and 'informed', especially when details matter. ;) I'm not even talking about using shielded wiring except for crank/cam. If you want to see overboard, check out what's involved in aviation spec harnesses.
And no, we're not currently planning to build a drop-on Miata harness.

I also took a few minutes to google drop on afermarket harnesses. I used LS1 as my barometer as it would be both extremely common and also use very normal connectors. Most of em were $1000, least expensive reasonable I saw was $600 for a "main" harness, and the verbage lead me to believe that other "accessory" harnesses may be needed. The Miata would be a less common application than GM LS1 by far, and the connectors would be much more difficult to source. LS1 connectors are dead simple to source.

You will have my response in PM, because this is beyond the topic...which is "what affordable high temp loom does Hustler need?".

Welcome to mt.net. We encourage tangents as long as they're roughly related and have content. Hell, it happens in half the threads JP decides to contribute to.

all good, I don't think I have my business model ready for scrutiny yet ;)

I already had to deal with this on the downshifting during daily driving LOL.

Decision is made. I'm using split loom and covering it in black silicone fire sleeve with silicone tape on the ends. This should look clean and improve the life of the loom and wires.