Battery Cable Length - How Important to Performance

[Rainman4820]

I am going to replace the battery cables on my 91 Marathon and while measuring them noticed that some cables are connected in a straight line to the next battery while others make a loop that doesn't look necessary.

Assuming the cables are routed with enough space to allow cap removal to check water level, avoid the obvious obstacles like terminals of other batteries, etc....is there any reason that they cant be shortened to go directly from one terminal to the next? In most cases the cable length would be shortened by no more that 25%.

[scottyb]

A shorter cable would be best, technically there would be less amperage loss although I doubt you could notice it performance wise. You will notice it pocket wire

[teecro]

No reason not to shorten where able, just keep in mind that short heavy gauge cables tend to "feel" stiff in that they may be harder to make the bend that you need without undue stress placed on the connection/terminal....

[JohnnieB]

The frame flexes a bit while driving, so the distance between the battery terminals changes and a little slack in the cables is needed to prevent terminal damage. The cables between batteries should be a gentle "S" rather than a straight line.

Also, the rear axle rotates a bit during acceleration and braking due to the leaf springs snaking, so the motor can move a couple inches forward and back during operation and the cables to the motor need some slack to prevent the terminals from being damage.

The cable should be as short as practical rather than as short as possible.

FWIW: 4Ga copper cable is 0.0002485Ω/ft.

[glassk]

Cable terminations are more critical than the 5 foot of cable you could end up with,...