[stent]

Anybody? How good is the ground from subframe to body? Should this be the 4th to make it The Big 4?
Huh, huh, huh? Come on, enquiring minds want to know!
I guess it's got to pass ground, but being it's mounted with bushings, does it have a separate ground?

from days of old i remember braided steel straps from the rear valve cover bolts to the firewall sheet metal on GM stuff, & ground cables from the battery bolted to the alternator bracket, but i dunno yet on the astro's, haven't gotten to the big 3 or 4 yet....... :shrug:

link to a little discussion i found : :text-link: https://www.astrosafari.com/viewtopic.p ... 0#p1564150

 

[Rod's Trucks]

AstroOaf....
You question about the engine to body ground has some merit.
Generally speaking...If the electrical ground path from the alternator( and engine block-usually one and the same), to the battery negative terminal should be just as substantial as the cables in the positive circuit ( alternator output to the battery plus terminal). If that ground path is exclusively a ground strap to the body, and then one from the body to the battery negative, then Yes, it should also be upgraded.
Many manufacturers have more than one ground path from the engine to the body and/or the battery negative, but the secondary one may not be able to handle the entire current when the starter is trying to turn the motor over. That is a commonly missed point when trying to troubleshoot a poorly functioning starter. I have seen three volts dropped through a badly corroded starter/engine ground cable connection. The insulation was burned off at both ends due to the heat being generated when a couple of hundred amps was being drawn through the resistive connection.

Both sets of cables ( the positive cable path, and the negative path) need to be sized to handle the same current (amps), when the battery is being charged; and similarly with the starter cables and engine ground cables when the starter is being operated.

The unibody ground will only need to handle the current that goes to circuits and accessories that are physically grounded to the actual unibody. That does include most circuits ( maybe ALL, on our A/S vans).
Rod J
Issaquah, WA

 

[WoodButcher]

Follow your ground from the battery, about a foot away it connects to the body, from there it connects to the block. That's all there is, if you feel the need to add to that down to the subframe fine, but why?
As far as I know there are no electrical connections to the sub-frame, for what? am I missing something?

 

[AstroWill]

It's a really short ground from the engine block to the battery, 50mm2 is the wire size, so it would handle 300+amps just fine.

 

[AstroOafAdventurer]

Thanks all, I get it now but couldn't quite grasp it before but the ground really only needs the beef for the starter.
For the equipment I'll be adding it will have it's own ground cable run.
Thanks, apologies for all my questions and impatience!

 

[AstroWill]

Thanks all, I get it now but couldn't quite grasp it before but the ground really only needs the beef for the starter.
For the equipment I'll be adding it will have it's own ground cable run.
Thanks, apologies for all my questions and impatience!

No need to apologize, this is how we all learn!

 

[WoodButcher]

For the equipment I'll be adding it will have it's own ground cable run.

There you go, ground to the body close to your appliance in an easily accessible place. I'll bet 50% of the issues I've found in my auto electronics history have been bad grounds. Use dielectric grease to keep the corrosion at bay.

 

[beaudryolivier4]

Hi everyone!

I am ready To buy a big3 kit on a website and they need to know this:

"To determine which length kit you need, measure the distance from the alternator output stud to the battery positive terminal taking into account a nice smooth run for the cable. For example, if you measure 3 feet 4 inches, you will need a 4 foot kit"



Do you know what is the length i need to buy?

Thank you very much

 

[Rod's Trucks]

I cannot help with the lengths, because mine was only a slight upgrade (with #6 cable I already had) some time ago.
Be sure the kit you are getting has the proper sized lugs for the cable ends.
Is this an Astro/Safari specific kit? If so, they should know what size wire, lengths and lug sizes are needed.
Rod J
Issaquah, WA

 

[beaudryolivier4]

Here is the link : Big 3 Upgrade Kits – Side Post Battery – CE Auto Electric Supply

Tell me what you think about it

 

[AstroWill]

I am ready To buy a big3 kit on a website and they need to know this:
"To determine which length kit you need, measure the distance from the alternator output stud to the battery positive terminal taking into account a nice smooth run for the cable. For example, if you measure 3 feet 4 inches, you will need a 4 foot kit"
Do you know what is the length i need to buy?

Why do you feel you would benefit from upgrading that wiring? Unless you have upgraded your alternator you really don't need to upgrade that wiring anyway. Check/clean/tighten your connections is usually all that needs to be done, are you having any issues that you are trying to fix?
Length depends on how you want to route it, going like stock down to the starter or all the way to the battery and the route you take will determine how long it needs to be. Basically you will have to determine what YOU want to do and measure it on YOUR van.

Even if you did upgrade your alternator there is already a huge, probably 1awg wire running from the battery to the starter, and then a smaller wire running up to the alternator, would really only have to replace that smaller wire going from the starter to the alternator. Upgrading alt you can order/buy a pre-made and terminated 4awg alt-to-starter wire for ~$15 that would be good for 200amps, can also check with your local LAPS/Cables/Audio places they can probably hook you up with a cable cheap.

Also, helps if you put your year/model/engine/AWD/conversion/etc in your signature line or your profile so we know what we are working with. https://www.astrosafari.com/account/signature

Here is the link :
Tell me what you think about it

For $100 or more I would definitely pass on that.

 

[Sailing_Faith]

Hi everyone!

I am ready To buy a big3 kit on a website and they need to know this:

"To determine which length kit you need, measure the distance from the alternator output stud to the battery positive terminal taking into account a nice smooth run for the cable. For example, if you measure 3 feet 4 inches, you will need a 4 foot kit"



Do you know what is the length i need to buy?

Thank you very much

4’ is just about perfect. Sure are a lot cheaper options though. 🙏🏼
I recommend adding secondary cables rather then replacing them.

2ga direct from the battery to the charge post on the alternator is a great improvement for the charge circuit….

If you buy a pair of pre-made cables in 2ga you can run the second one from the alternator bracket to the body ground

I used a 2/0ga cable from the battery to the chassis ground (had it on hand).