Gilbert! I miss Gilbert. Grew up there. Others have already said, hook the positive to the starter. Ground wires:

• Battery to body (You got that)
• Body to frame
• Body to engine
• Frame to engine

An additional negative cable direct from battery to engine isn't a bad idea either. The more connections the power has to flow through, the more resistance and greater chance of disconnect. Remember the drivetrain, body, frame all have rubber mounts between them. What I suggest may be overkill, but it will keep you from having weird electrical problems.

 

Agreed. The Optima emits less gas than a typical lead/acid battery. Additionally Optima has filters on the vents that are supposed to react with hydrogen and turn it to water. HOWEVER, it is a slight risk. if the filters on the battery fail, the trunk can fill with hydrogen and interesting things will happen if it ignites.

 

actually you're not only moving 40 lbs to the trunk but also adding heavy weight 1 or 2 guage wire. i also have a dd that i take to the stip maybe once every 2 months. lightweight 9 lb battery off ebay for $37 & works perfect starts my car up as if it were a 35 lb 700cca battery, yet i REMOVED about 22 lbs & added no heavy wiring, & when i do go to the track i'm perfectly legal. you guys on the other hand, unless your battery is in a sealed box & has the proper cutoff switch, will not get to run your car if you decide to go to the strip. just my 2 cents

 

I would also suggest using a 4 post cutoff switch with a feed running to the alternator. The diagram posted earlier with a 2 post switch would leave the 4 GA wire running to the alternator hot, which would not be a good thing if you ruptured a fuel line and that wire found a way to spark against the chassis. You could also use a bulkhead to isolate the trunk instead of a sealed/vented box. NHRA rules don't specify the difference between sealed and non-sealed batteries anymore, they're all treated the same.

 

I'd rather just run a lightweight up front personally. No additional wiring, no holes drilled, no box, no cut off switch, no vent, etc. If you're truly concerned with DDing a small battery, swap in your regular size for everyday use and swap in the smaller one when hitting the track.

Also you don't have to worry about some jackass yanking on your kill switch when the car is left parked.

 

I do enjoy my upgraded wiring over the factory crap. I also enjoy weight behind the rear axle. I've never had tech look at anything on my car, just asked what tires I was running. Sub 10 second cars require a cut off switch at the rear of the car as per nhra rules.

 

I mounted my cutoff on the rear facia?(the pice above the bumper cover that says Camaro. I ran my ground to the trear upper seatbelt lug. hasa noce spot to attach. I ran my hot under the hood on to p of the frame rail using a heavy isolated lug. From there I can run to the other hot lug and the starter. il run a heavy ground from engine to frame when I get the engine in. Ran wire from the alt to the live side of the cutoff switch in the rear