trunk mounted battery

We use a ground cable from a welder as the power cable. It is a braided copper line which makes it more flexible and easier to route from the trunk to the engine compartment. We bought our last one from Tractor Supply.
 
We use a ground cable from a welder as the power cable. It is a braided copper line which makes it more flexible and easier to route from the trunk to the engine compartment. We bought our last one from Tractor Supply.
Did you run a dedicated ground wire back to the battery, or did you just ground to the frame?
 
Did you run a dedicated ground wire back to the battery, or did you just ground to the frame?

This was a long time ago in my old dodge charger, i just bolted the ground to the frame in the trunk. When i went to start it , if fucked some major shit up jumping spark trying to find a ground. Run a dedicated ground cable .
 
I just ground to the frame with a welded on stud,and make sure I have a heavy ground strap from the block to the frame.never had any issues

DId mine the same way on my car for 6 years no issues.

It is MUCH better running a dedicated ground and using a central grounding point. SPecially if you're going to have electronics in the car.
 
Mine is complicated...due to alternator shut down relay switch involved plus mega-fuses inline with power to distro box.
 
Did you run a dedicated ground wire back to the battery, or did you just ground to the frame?

I just ground to the frame with a welded on stud,and make sure I have a heavy ground strap from the block to the frame.never had any issues
We ground the battery to the frame in the rear and pick the ground back up on the frame in the engine compartment. Make sure you run a ground to the engine block and to the body
 
i mounted battery box in trunk, mounted switch in decklid and to be nhra legal you must have an alternator shutdown. SOOOO this is how I ran my...i used painless wiring alternator shutdown kit..but added 150amp relay from disconnect switch going to alternator relay. this is the diagram
then ran a power wire from battery to power distr box

hopefully you can see it clearly. I will post some pics of my set up if you like
 

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i mounted battery box in trunk, mounted switch in decklid and to be nhra legal you must have an alternator shutdown. SOOOO this is how I ran my...i used painless wiring alternator shutdown kit..but added 150amp relay from disconnect switch going to alternator relay. this is the diagram
then ran a power wire from battery to power distr box

hopefully you can see it clearly. I will post some pics of my set up if you like

please do if you dont mind
 
i mounted battery box in trunk, mounted switch in decklid and to be nhra legal you must have an alternator shutdown. SOOOO this is how I ran my...i used painless wiring alternator shutdown kit..but added 150amp relay from disconnect switch going to alternator relay. this is the diagram
then ran a power wire from battery to power distr box

hopefully you can see it clearly. I will post some pics of my set up if you like

IMO this is the way to go if running EFI. Little extra wiring, and steps, but much more reliable in the end.
 
i mounted battery box in trunk, mounted switch in decklid and to be nhra legal you must have an alternator shutdown. SOOOO this is how I ran my...i used painless wiring alternator shutdown kit..but added 150amp relay from disconnect switch going to alternator relay. this is the diagram
then ran a power wire from battery to power distr box

hopefully you can see it clearly. I will post some pics of my set up if you like

So, the 150A relay opens when you hit hit the battery disconnect.... clever, now the alternator can't supply power to keep the engine running. Where does the alternator shutdown kit come in?
 
Reply #2.. sorry, the 150A relay you have IS part of the Painless kit.
So, the main battery lead to the rest of the vehicle wiring is controlled by the relay as well, or just not shown in your diagram. I'm wondering about retained accessory power and the like. When we put my friends car on the trailer, we usually hit the battery disconnect as well, what I never really thought about is that when you disconnect an EFI car, you shut the ECM off completely, and all learns are wiped out.

Can I just get a Ford-type starter solenoid and accomplish the same thing? Or do those not like to be energized for a long time?
 
Reply #2.. sorry, the 150A relay you have IS part of the Painless kit.
So, the main battery lead to the rest of the vehicle wiring is controlled by the relay as well, or just not shown in your diagram. I'm wondering about retained accessory power and the like. When we put my friends car on the trailer, we usually hit the battery disconnect as well, what I never really thought about is that when you disconnect an EFI car, you shut the ECM off completely, and all learns are wiped out.

Can I just get a Ford-type starter solenoid and accomplish the same thing? Or do those not like to be energized for a long time?

Ford ones are NOT long term solenoids like the painless one. THe other question is a good one? Do you really retain the learns on a custom tune? Maybe a dedicated wire to teh keep alive circuit?
 
So, the 150A relay opens when you hit hit the battery disconnect.... clever, now the alternator can't supply power to keep the engine running. Where does the alternator shutdown kit come in?
yes..it come with the kit....
 
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IMO this is the way to go if running EFI. Little extra wiring, and steps, but much more reliable in the end.
yeah...with the amount of time and money into a project I didnt want to take any short cuts with wiring. I will post the pics of my set up as soon as I get back into town
 
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