Wiring Stupid Question

**zuludan** · 17-05-2008, 08:21 PM

Hey Guys,

I know this is probably a stupid question, but I am about to do a fair bit of rewiring in the RA23 and was wondering what sort of wire should I use. Eg 15amp or 25amp wire.

Another question is and this could again be another dumb question. Is there any rule or best practice I should stick to in wiring colours. Eg Yellow for constant power, Red for power from a switch. Black as Earth Etc. Blue and Green - Who bloody knows

Another not so dumb question, If rewiring sensors, is there any special types of wire and things to avoid ? Eg Too much bare wire or cuts in the wire.

Thanks

**Gavatron** · 17-05-2008, 08:23 PM

Wiring size depends on the length of the wires, how much current they will be carrying, and whether they are in a loom or just a single wire.

Some sensors, like knock sensors and 02 sensors, have shielded wires.

**zuludan** · 17-05-2008, 08:28 PM

I wont be extending any wires by any considerable length at this point. I am pretty much rewiring the standard RA23 wires. The main reason for this is too hide wires and I am moving a few things around in the engine bay and behind guards.

Eventually the Battery will be moved to the boot.

**LeeRoy** · 17-05-2008, 11:00 PM

Yor best bet is to use the same size wire as standard and also continue to use the same size fuses. If your not increasing the current the wires need to carry this will be fine.

If your upgrading the lights then those wires and fuses will need to be upped in order to cope.

Your 2 formulas which will determine wire size will be V = IR (volts, current in amps, and resistance in ohms) and P = IV (power in watts, and current and resistance as above)

Even if you tried to only use specific coloured wires for specific things the availability of a variety of aftermarket coloured wires is very narrow and youll probably find you can only get wires in black, red, yellow, white, blue, green, and maybe a couple of others. These will more than likely not be available with a trace colour either unless you plan on spending a decent amount. If your after more colours then maybe get yourself some looms from a wrecker to pinch them from.

New plugs for your car can be bought from supercheap, repco, bursons etc and jarcar will also have some other things you might need. Wire can be bought from all of the above.

If your repinning plugs then youll probably want to either borrow or buy some crimpers (not pliers), and also have the usual supplies like solder and soldering iron, tape, cable ties, heatshrink, etc.

**zuludan** · 17-05-2008, 11:41 PM

Thanks for the reply, I have all the tools, no issue there. I guess my question is what is the standard wire amps capacity. I am going to leave fuses as they are; as well as headlights. Things that are being moved are wiper bottle and coil

**LeeRoy** · 18-05-2008, 02:01 AM

Use the fuses as a guide and work out the required wire capacity that way. Fuses must be smaller than wire capability.

**turbo ke20** · 18-05-2008, 01:26 PM

most wires are now rated in size. Id use 3mm on all the switching side of things and engine sensors etc... then 4mm on the load side eg..headlights, fuel pumps, thermo fan etc. then 6mm for battery supplies to fuse boxes and the alternator power supply.
and dont be shy with earths. the more the better.

hope this helps.

**Mos** · 18-05-2008, 01:33 PM

Originally Posted by zuludan

I am going to leave fuses as they are; as well as headlights. Things that are being moved are wiper bottle and coil

I would strongly urge you to take the time to redesign the loom rather than just rerunning the factory setup. Headlight wiring on virtually every factory car leaves a great deal to be desired and even factory wattage bulbs gain brightness by running direct wiring.
I realise it's a level of complication above what you were going into, but you will rarely have opportunities where you can "fix" the factory compromises.

Mos.

**big_zop** · 18-05-2008, 01:45 PM

Also make sure you draw a proper diagram so that you can fault find and modify later. There is nothing worse than having to go through all this trouble to make new looms to have no idea what you have done when it comes 6 months down the track and you want to add something to it.

Make sure you have a good read of Phil Bradshaws site as although there could be improvements and im not sure if it will have EFI (not too knowledgable on the old school stuff) - its a good base to work with and confirms some of what has already been said.

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