Automotive connectors

What do other people use for the interior connectors (eg between main loom and sub-looms for dash/instruments/switches etc)?

I was thinking the TYCO Mate-N-Lok, Available in 20A per pin, 10A per pin and 5A per pin versions.

5A Mini Mate-N-Lok - Up to 15 way - Picture and details from Mini Universal 'Mate-N-Lok' Connectors

10A Mate-N-Lok - Up to 15 way - Picture and details from Mate-N-Lok - Universal Connectors

20A Mate-N-Lok 3.5mm - Up to 9 way - Picture and details from Mate-N-Lok - 3.5mm Connectors

Bill Musarra

Those look very nice. The trick for any set of connectors is how well they crimp and install into the connector(and remove from) and how easily they connect to each other. I would suggest ordering a few different types of their connectors and trying them out at the work bench. Trying to do this in the cramped confines of the footwell is not when you want to find them a PIA. That is why I stick with the "weatherpack" brand of connectors. Easy to do all the operations and only rarely run into a hitch.

That is why I stick with the "weatherpack" brand of connectors. Easy to do all the operations and only rarely run into a hitch.
The Weatherpack are very similar to the AMP 'Superseal' ones. My issue with those is the number of pins as they seem to max out at 6 , I'm looking for ones with more connectors.

Those are AMP 'Superseal' ones (or copies), again they max out at 6 pins.

The 6.3mm ones or the Mate-N-Lock? (I'm not sure if they are really Mate-N-Lok or knock offs)

I'm not happy with the VWP lack of details on the maximum amperage for the 6.3 multi-connectors, I'd guess at 15A per pin though which is less than the 20A for the Mate-N-Lok.

Unless anyone has anything better it looks at least that I'm not missing something obvious and there is nothing appreciably better than the Mate-N-Lok, so I think I'll use them for the interior wiring and either superseal or weatherpack for the 'external' connectors (engine bay, under front clip, anywhere that could get wet etc). I'll grab a few of both the superseal and weatherpack and see which ones are easier to assemble...

Thanks all.

EDIT: I note that the Mate-N-Lok are also available with splash/waterproof (IP56/IP57) seals - eg
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Bill Musarra

One I didn't mention is the weatherpack pass through connector. Meant for firewalls etc. It has 22 pins. Some are for small wires and others for larger wires. You can view them here:
Weatherpack Bulkhead Firewall Connector Kit
Most of the weather paks will handle up to 20 amps. For me most of the things that require above 15 amps will get a relay and will get the power wire to the appliance without any connector except to connect the appliance or it gets soldered and shrink wrapped. They have a fuse of suitable rating in the fuse block. Most of my big power users are in the fuse box(see below). For the things in the box that I was not going to use I redireted them to the big power users. For all the appliances that required relays, I built an accessory fuse box(and terminal strips) and housed them all together. I housed both fuse boxes in project boxes from Radio Shack. There are several good setups like these:
Painless Performance
Highway 22 Panel Wiring Kit We Make Wiring THAT Easy!

If you want I can post pics of how I set them up.


Howard Jones

First the white plastic connectors are of minim quality and are not intended for use where they will be disconnected from each other routinely. Specifically, the type of pin that are used is not intended to be removed from the shell once installed. This may or may not be an issue but "one time incursion" type pins are typically not of high quality or reliability. On the other hand they are very inexpensive. Really, really cheap in fact.

Weather pack type connectors are intended to be used to disconnect sub assembly's (fans for example) from time to time and generally work well in automotive environments. I like them and intend to use them in several places on my SLC. The one disadvantage can be that they only have connectors with up to 6 circuits, with the exception of the big round one pictures above.

SOOOOOOOO......... I offer this alternative. They are plastic shells but use real professional grade pins in the connectors that can be removed with a insertion and removal tool. They also have really endless choices as far as pin numbers, sizes, shell configuration etc. and they are not real expensive like their mil spec metal shell cousins. They are a bit more expensive than weather packs however but worth it IMHO.

I am going to use at least one big one to connect the dash board harness to the chassis harness on my car. This will be something like 20 separate circuits. More than likely I will use two connections of about 8-12 each. One being a larger connector with a smaller number of big pins to supply power and another to run signal circuits like temp sensors.

Here is a example and a start point to do your own research. If you go to the catalog page you can begin to sort through the choices. Stay with the type 1 connector series and you will be OK.

TE Connectivity - 206037-1 - Circular Connectors - Circular Connectors - Allied Electronics

Maybe the best bet is to go to the Allied website and have a look. This is a very good source for electrical parts by the way. In many cases the min quantity will be cheaper than buying one piece from a hot rod store.

Here's a good place to buy weatherpacks in quantity's that are useful to a complete build. You can piece each connector out and get just what you want.
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I'll second that. The Tyco circular connectors with Series 1 pins and sockets are very good and work with a variety of core and insulation sizes. However be prepared to spend time with the catalogue to spec the parts. The only drawbacks are that they are not waterproof and you will need special crimp pliers. A degree of waterproofing can be achieved with silicon in the back of the socket where the wires enter. The crimp pliers are specified in the Tyco catalogues but are eye wateringly expensive but can be found second hand.
Roger Allen
Wow! Yeah, I think the Mil-spec is a bit OTT.....

...says the man who got Aeronautical/Mil-spec TZL wire for the engine bay due to thinking a maximum temperature rating of 105°C was a bit low for running next to the engine. :)