So, I have a trunk mounted battery, and am running a 2 gauge positive & negative up to the starter. Then from the starter I have grounding straps to the frame/and engine. My question is can I tap in some of my accessories off this connection up at the starter, or do I need to run another (smaller) cable back to the battery? Want to make sure I do this the right way. Thanks for any input
That's how mine is, if there is a down side it hasn't shown up yet. Everything is powered from the starter solenoid terminal.
Both GM and Ford pulled all power from positive cable solenoid connection for ever. Don't think you can go wrong there. The Wizzard
The drawback is that the accessory will get less voltage while the engine is cranking, because of the voltage drop in the long cable. This will generally not cause any problems, but without knowing what you are planning to connect, we can only guess.
My Plymouth takes power from the battery side solenoid terminal for the main power feed for the car. You didn't mention if you are talking 6 or 12 v. If 6v I would use a 00 gauge cable on the load side, 6v depends on current flow so when in doubt go thicker.
12 Volt. Running 2 gauge for both positive/negative. Each is about 7-8 ft or so of wire. If anything I will run a higher gauge wire up into my maxi fuse straight from the battery rather than from the starter.
I use welding cable for battery power. I think 0 gage. I have used the frame for ground in the past, but this time I used cable for ground back to the block. 8 gage for power from the starter to fuse panel. Sent from my iPhone using H.A.M.B.
Let me clarify "6v depends on current flow" I believe you meant to say "6v depends on HIGHER current flow" In order to deliver the same amount of wattage to the starter, a 6 volt system will need to deliver twice the amount of current as a 12 volt system. In order to handle the higher current, battery cables with a larger conductor cross section are required.
The cable size is plenty big enough to power all your non-starting loads, but may prove to be a bit skimpy when starting, particularly in a hard-starting scenario. I'd bump the size up to 1/0 to be safe.
Is there a benefit to running a dedicated ground wire? Why not just ground to the frame as close as possible to the battery? How do you go to ground for item normally grounded to ch***is or body?
^^^ As mentioned above, 1/0 would be a better cable size choice for a trunk mount battery. Sent from my Nexus 5X using The H.A.M.B. mobile app
Frames have welded connections, each weld and each connect can effect the current flow over time, so the less connections, the better off you are. If you plan to power the car from the battery, be sure to fuse the wire at the battery, if for some reason the wire was to short out up front, the fuse will blow out at the battery and you won't have a smoking hot wire the whole length of the car. I to would boost the battery cable size up to 0 or 00 size, #6 may not work with a hot motor and interior fans or accessories on. I come from a school bus mechanic back ground and they all use 0000 cables, we use #6 cable just to power the A/C systems.
Check voltage at battery and at starter. This will show what is being lost in long cables. I used 00 in a '46 Ford with trunk mounted battery. You never go wrong with a bigger cable than you think you need.
Joel is right on everything. There are millions of cars moving down the road taking power at the starter terminal. Running a separate ground cable to the block is also a great idea and you can't have too many ground straps, lots of places carry the braided types that look good and are available in multiple lengths.
I run a Ford solenoid on my firewall (have a GM starter/solenoid downstairs) and I take everything off the firewall solenoid. My battery is under the hood and I use welding cable, probably 2/0.
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