I am going to move the battery out of the engine bay to clean things up, it’s going in the storage bin behind the drivers seat. I am going to get a Optima red top and i was thinking of using 4 ga. cable. Is 4 ga. big enough? I don’t have any extra accessories like amps or anything else drawing extra current, I just want the best power transfer. Let me know if anyone has some input.
was pretty sure it cant be in the passenger area, gotta be in the trunk and properly secured?
anyways, they sell relocation kits for like ~$100 at summit racing might as well grab one of those
its not the passanger area. rx7’s don’t have back seats theres rear “storage bins” so its not exposed
as long as it is in a sealed batt box or is a sealed battery it is fine, legally. i’m just wondering about wire size.
most kits i have seen use 2g, this is most likely what ill use on my car, im sure you could use 4g but it may cause more voltage drop than you want
The kit I bought uses 1g for the power and ground wiring. I would recommend using at least 2g, as you might see more drop than you want with 4g, especially if the ground isnt perfect. Advanced auto sells 2g by the foot and it isnt too much.
looks like i’m going with 2 ga., its 2 bucks a foot at parts express.com, it will be safer in the long run. thnx for the input.
I used welding cable for my run… Its less expensive.
In any case, SEAL both ends of the cable with epoxy once its bolted in place. I sealed around the perimiter of the ground mounting foot too but Im thorough like that.
1/Ott for less then what local “shops” sell 4ga. for.
Are you suposed to run a ground wire as well or jsut ground it to the frame?
I’m just running it back to the stock ground lead.
ground to the frame.
advantages?
most important one - less resistence…
less wire, which leads to less cost, and less time spent. but, more importantly, refer to 1st mention.
assuming You use 4awg that’s 20’ in length and draw 80amps rms - You have a ~0.4 volt loss to wire resistance.
where as 4awg thats 3’ in length and draw 80amps rms - You have a 0.06vdc loss.
also, less wire = less weight.
I’d go with something heavier than 4ga. Grounding to the frame is perfectly fine too. Both of my BMW’s had/have trunk mounted batteries from the factory, both are grounded right in the trunk with like a 6" cable.
We put Xanders in the passenger side box, most of the time your driving around alone, put the battery oposite the driver, just a thought. 1ga was used, and you should want to keep the ground as short as possible imho. I am pretty sure there was a decent place to ground in there. I made up an aluminum bracket to out of some flat stock to hold it down, and trimmed the inside of the box to fit around the battery and look pretty decent. Good luck :tup:
Jeller
ok, so it’s going to be 2 ga. and a short ground to thte underside of the car just under the battery. Should i ground the factory battery ground to frame up front as well?
doesnt really matter. will make no difference either way.
Your chassis ground should be bolted to heavier panels… preferably where they are sandwitched together and have some thickness.
Put a crimp terminal on the alternator end:
-Put a very thin coat of soldering flux inside the terminal and on the stripped wire end.
-Stick the wire in the terminal.
-I crimped mine by driving a drift pin/punch into the center ofthe terminal. If you angle the pin it creates a nice tab that works like the one is a zip tie. Crushing the entire terminal of that size looks like shit.
-Heat the terminal with a HOT torch and feed solder into the end till it fills. By having a hot torch you can do this relatively quickly without heating up the wire too much. i used a propane job and it worked well.
-Clean off the teminal with acetone or something and seal the joint between the wire insulation and terminal with “JB Weld”
-Put grease on both sides of the terminal before you bolt it to the starter.
If water ever gets under wire insulation it will ruin the wire and your entire job. JB Weld works nicely. Even tho it looks thick it will creep as it cures. Set the wire end in a vertical position so the creep is even. Flip in every 15min for a hour and you will get a nice finish.
Yes you should ground the factory ground wire to the frame. You want to make sure the engine and all ECU electronics have a good ground. There are ground points for various sensors on the block which is seperated from the frame by the mounts.