Size of wires used in engine looms

[Sam_Q]

i am re-wing some of my engine loom and I was wondering what size wires goes where. I did find a thread on this however they used the non standardised auto sizing which means nothing to me. Does someone know what size cables to sensors, injectors and other components?

Answers only in square mm please.

Looking at my 20V loom the wire conductors look seriously small, something like 0.25mm^2., however it is a custom loom.

For the part I want to rewire I have some 0.5mm^2 cable which I am thinking of using for all the sensors. I think this is rated for about 4A.

Using some 1.5mm^2 cable for ground leads and maybe injectors, its meant to be able to handle 12A. What do injectors suck?

Is my cable sizing ok?

[Sam_Q]

I had an idea, I have a chopped up 20V loom, what I can do is measure the diameter, work out the Cross sectional area (CSA) and then post my results on here

[JustCallMeOrlando]

Perhaps it would be better to match it to a gauge as that is what people can most commonly relate to.

[Hen]

Low impedance injectors (without a resistor pack) pull up to 4A while opening and then about 1A while staying open.

High impedance injectors (or low impedance injectors driven through a resistor pack) pull around 1A.

Sensors don't really need any current so you can run pretty small wire. And that 1.5 square mm cable sounds like it should be able to cope with most things.

Hen

[Wiggles]

Ooh, let me know what the diameter/CSA/Gauge you end up using, i'll need to know this when i get around to doing my conversion in a few weeks/months/years

Conversion Table showing AWG Gauge vs Diameter (in) vs Diameter (mm) vs CSA can be found Here

[Wiggles]

Also, Were do you buy bulk wire for this type of job for a reasonable price?

[bobob]

I have been thinking about doing this soon, my last conversion I did with what ever wire I could find. I thought that one day I would get around to 'neatening it up'. You may have heard of 'black wire alarms' this turned out to be a simlar approach.

Instead, because it runs fine, I have gone and bought another car. I will get the right wire before hand this time, I remember seeing this helpful page regarding the wire subject.

http://www.toymods.net/forums/showth...highlight=wire

these guys sell it at reasonable cost in a large number of colours..

http://www.castleauto.com.au/wiring.htm

and

this is the place, they have rolls of wire in all different colours

Auto - Electrical Parts Supplies
Cnr Moss St & Pacific Hwy
3208 5533

Good luck

[JustCallMeOrlando]

For my wiring I went to Jaycar and purchased a pack with like 8 rolls of different coloured wire. I've used it for quite a few things now and served me well.

[bobob]

I would really like to be able to keep the toyota colour scheem. It grew on me after staring at the mess for so long!

I hope to one day obtain wire that allows me to do that, and not have the insulation melt in the process.

[Sam_Q]

this is what I am buying: look at number 5

http://www.oatleyelectronics.com/cable.html

heres what it gets you:


4M of 1.5mm^2 red and black
3M of 0.5mm^2 yallow and purple
3 to 4 nice inline blade fuse holders
3 to 5 inslated blue spade crimp lugs

all for $1!!

you better get in quick though becase I might have bought whatever was left. Also the world price for copper has doubled so explect some serious price rises soon.

I do want to check what my standard loom is and I will give it a go with the micrometer and post it here.

The wire that Jaycar sells in 8 colour rolls is cheap but its only 0.15mm^2 which is only rated at 1.1A. Now I know this is theory could cover almost any sensor/relay but there is also the issue of volt drop. The higher the current draw the higher the cable. But I may be wrong and that sensors require so little they only need 0.01mm^2 cable. How did you find the result on your wiring JustCallMeOrlando?

[Sam_Q]

Also thanks for the info wiggles and Hen, here is a summary:

Gauge : Wire size (mm square)

0000----107.16
000------84.97
00--------67.40
0----------53.46
1----------42.39
2----------33.61
3----------26.65
4----------21.14
5----------16.76
6----------13.29
7----------10.55
8-----------8.36
9-----------6.63
10---------5.26
11---------4.17
12---------3.31
13---------2.63
14---------2.08
15---------1.65
16---------1.31
17---------1.04
18---------0.82
19---------0.65
20---------0.52
21---------0.41
22---------0.33
23---------0.26
24---------0.20
25---------0.16
26---------0.13


As a rough rule every mm square of cable can handle 7.5 Amps continous.

Lugs are also available for larger cables in places like Middys, they store I visit even can crimp it for me, which would be handy if I didnt have a monster crimper for 16 to 75mm^2

The difference between normal cable and OFC (oxygen free copper) is that the OFC cable has a slightly lower resistance, but it's minimal

[Sam_Q]

Here are the insulated lugs available through electrical suppliers in mm square:

1 - Red insulated
2.5 - Blue insulated
4 - Yellow insulated

then after that are uninsulated lugs, they come in these sizes:

1
2.5
4
6
10
16
25
35
50
70
95

[Sam_Q]

oh forgot to mention Jaycar sell some nice 1.0mm cable. Here are the details:

"heavy duty"
WH-3040 = Red
WH-3041 = Black
WH-3042 = Solid green

all are $0.40 a meter or $25 for 100M, this should be able to handle a constant 7.5A, I know it's only 3 colours but it's a start.


Repco have reels of cable in 10 different colours also that look to be 1.0mm, I bought 3 meters of each and it cost me $12 trade.

[thechuckster]

i've found that:
-trailer loom is ideal for carrying a large number of high-current circuits - 7 or 8 wires that are colour coded and sheathed
-jaycar sell a heavy-duty 4-wire shielded ccble (ostensibly for audio) that's ideal for running your 02 or TPS signals
-the only circuits that should be high current (e.g. over 1 amp) all the way to the ECU are the injectors (PMW-controlled valves like idle or boost-control need about 1A max so they can be smaller) - so don't go overboard with wire core sizes
-shield the TPS and O2 signals - these are prone to interference - they're also low current.
-earths are pretty damn important - don't skimp on good earth contacts!

cheers,
Charles.

[Wiggles]

Cheers for that chuckster.
BTW, shouldn't you be at the gokart track like it says in your sig?