KRRZ350

iTrader: (29)

Arrrrgh, I think I messed up installing one of these.

After putting the junk in the trunk, trying to follow NHRA rules & installed a master disconnect switch above the tail-light. It's all wired up & works perfect, but I can't run the car just yet, and I have a sneaking suspicion that when i do the switch won't work because I didn't also run a separate wire from the alternator to the battery, I just went from B+ to switch and then from switch to existing + wire in engine bay. Am I correct that wired like this the car will continue to run even if the switch is hit?

If what I believe is correct, is there a cheaper way than having to buy another 15' of heavy gauge wire and more large fuses?

Also, one more question, can anyone confirm that a 5.5 gen Maxima trunk is not consider a seperate bulkhead? The plastic battery box we used isn't approved by the NHRA.

EsQueue

iTrader: (2)

As for the question, I don't track so I have no clue what you are reffering to. If it was an emergency cut-off switch, I don't see why the ground wasn't the kill point. Just as I said, I don't know the rules or reason behind this.

Just guessing here but what about a heavy duty realy instead of running more large wires?

KRRZ350

iTrader: (29)

Yup, rules also state that you can't use the ground

Relay sounded perfect to me for a second, but after some more thought I don't think that will work since either side of the switch will still see power (Either from alternator or battery), I think I'm just going to have to run more large wire & fuses.

KRRZ350

iTrader: (29)

Any chance a mod could move this to the 1/4 mile forum? I meant to post it in there not here, ooops.

98SEBlackMax

iTrader: (9)

Well since I am making one of these kill switch setups for my car and I am feeling generous. I will tell you there is an easy solution that doesn't require big wire.

First off you have to make sure the switch is NHRA approved. This switch is and has the certs for alot of other clubs.

http://www.racerpartswholesale.com/p...ry_Disconnects

Secondly if you look at the electrical charging schematic of a Maxima (well at least on the 4th gens) you will see there is a wire that connects to the battery then goes thru a 7.5 amp fuse and then goes to the alternator, this is for the battery indicator circuit. This is exactly what it looks like, it tells the alternator that the battery is hooked up and when it sees 12 volts it activates the charge circuit in the alternator. If this fuse or wire is not hooked up the alternator WILL NOT charge.

How do I know this? I had a local org guy who kept killing batteries and the local idiot shop get swapping alternators but his car would not hold a charge for more than a few minutes. I ended up finding this 7.5 A fuse was missing for some reason and replaced it, the alternator started charging the instant I put that fuse in!

You will need a disconnect switch that is a DPST, meaning double pole single throw. Use the big terminals for the battery and the small terminals for the charge circuit.

Battery - 2~4 gauge wire - 150 amp fuse - disconnect switch (big terminals) - 2~4 gauge wire - alternator primary wire or the battery post wire

150 amp fuse - 18~20 gauge wire - 7.5 amp fuse - disconnect switch (small terminals) - 18~20 gauge wire - alternator charge wire

You can remove the OEM charging circuit fuse (Fuse #60 on a 4th gen) once it is all wired up. IIRC some other circuit might use power from this fuse but I'm not 100% sure. On the FSM I have there is no other use for that fuse, but I haven't looked over the entire electrical schematic yet.