Starter Solenoid Wiring Question

[71Demon340]

I bought a Mopar mini starter and was looking at the new solenoid plug and wire pigtail that came with it. Why is the wiring on the new connector so much smaller than the factory wire? I've relocated my battery to the trunk so I will have a new battery/starter wire and solenoid wire. Should I decrease the size of the wire from the solenoid to the relay to match the size of the wire on the new connector? Thanks.

 

[chasduster]

you are going to want a good size wire from battery to the starter 4 ought...For the hot leg....and 10 gauge should be plenty to fire it from the selonoid

 

[71Demon340]

Batt relocation kit came with either 2/0 or 4/0, so I'm OK there. Factory solenoid wire is around 10 ga. Pigtail on connector that came with starter is probably around 14 ga. Just wondering why there was such a difference.

 

[chasduster]

Oh who knows with the aftermarket stuff out their....14 gauge is probably heavy enough...but if you have to run wires why not go 10 and just install a larger connector...

 

[RedFish]

I'm guessing you are refering to the wire from starter relay to bendix drive...
same size wire is found between battery and starter relay. The only fuse in the line is the gauge of that wire.

 

[71Demon340]

Connector is specifically made for the starter, like a modern factory plug. Haven't really looked into whether it can be modified for a heavier wire.

Thanks for all the input.

 

[cudajim]

The small wire only supplies voltage to the bendix coil and it does not draw that much current so any voltage drop is negligible. The large gauge wires on the other hand need your attention. If they're too small you'll get too large a voltage drop by the time you get all the way from the battery (in the trunk) to the starter due to the large amount of current the start needs. E=IR (ohms law) always comes into play.... that is voltage and current are inversely proportional.

 

[71Demon340]

I've never seen it expressed as E=IR. I'm familiar with V=IR and P=VI or P=(I^2)R. Anyway, I think I will use same size of wire on connector all the way to the relay. A friend of mine said that the reason for the large original wire was because the old bendix starters pull a lot more amps than the new starters. I am running a 6 ga wire from the relay to the batt for the charging wire.

 

[cudajim]

I've never seen it expressed as E=IR. I'm familiar with V=IR and P=VI or P=(I^2)R. Anyway, I think I will use same size of wire on connector all the way to the relay. A friend of mine said that the reason for the large original wire was because the old bendix starters pull a lot more amps than the new starters. I am running a 6 ga wire from the relay to the batt for the charging wire.

Look at some older electronics books and it's always E for voltage. It was changed to V later on as it probably confused many people so I guess V became the standard. In any case it's just a variable name so V (for volts) works for me.

I checked the charging system on my 67 Barracuda last night and it was not pretty. I had a voltage difference of 1.3v between the battery + terminal and the alternator output. I expected up to .5 but not what I got so I will probably tear into it, beef up the wires and not run through the firewall/ammeter. I'll check my headlight voltage next.