Guys, I'm one of those guys that is a stumble block head when it comes to electrical stuff.
Lighten a car? you got me 110 percent.
Electrical? Blackout.

Right now, I've got my battery grounded to the frame (clean connections and all) with thick 00 cable and then my engine block is grounded with waived ground straps in two places up front. My hot cable from the cut/off switch-battery goes to the front firewall where it is connected to a junction box or terminal box and then from there to the starter. Is this good?
Is this thread about the MSD or any ignition box not getting all the juice it could? or is this just all about starting?

2/0 high quality cable/wire from the (-) battery lug, directly to the engine block. from that point, fan off of that to your solid copper ground bar/strap for all of your negative connections.

I prefer 2/0 Anchor copper cable. You can buy it from West Marine, however make sure to have the battery lugs crimped on with a hydraulic lug crimper, and use the Anchor heat shrink.

Since current flows from negative to positive, your ground/negative cable is very important. Also, ground the battery to the frame in the trunk as well.

I also prefer to use the Ford style solenoid to attach my Positive cable from the battery switch to this solenoid. That also includes a 2AWG from the main positive on the solenoid lug to your Positive junction point for all of your electronics. Making sure that the junction his also high quality Copper.

Good luck...Mark

That`s how mine is and it cranks/starts fine and charges at 14.7 when it fires...........I also use a Ford relay directly to the starter.......

It may work fine.......and that may be the way many people have done it since the beginning of time.........but it also doesn't mean there isn't a better way. The chassis itself is a POOR conductor of electricity

appreciate everyone's help. I pulled the trigger on a 21 lber. An 18 lb loss in weight. Also have some lightweight negative cable on the way. I've never had any problems but I'm going to listen to Monte and run a ground up front

Depends on the chassis. A unibody might be a poor conductor but anything with a cage in it should be just fine. Even a set of frame connectors will tie the rear subframe to the front subframe and give the battery a low resistance ground path to the front of the car. Easy enough to check with an ohm meter.

Well, I'm in the lottery then because I have both subframe connectors welded in and a 12 point roll bar welded in.
Hemi-itis today by the way mentioned the roll bar/cage as being a good ground to think about.

Good point. Perhaps uni-------bodies that are not tied together (ie: Restored or original muscle car chassis)would probably benefit from not having any undercoat applied or it doesn't matter?

One thing I do know is that when ever I perform any welding duties on the car itself, I disconnect and remove entirely the battery, Alternator and especially the MSD ignition box.

People who know way more than me, have told me that a chassis, even a full tube chassis, is a very poor ground connector. Top level cars are NOT wired that way. They are wired with a "floating ground" and the chassis is not part of the equation.

Monte, I agree 100%. But did you notice on the Challengers, Chargers, 300's, the batteries are in the trunk and they all have the thinnest ground wire you've ever seen screwed to the frame rail. The Jeep Grand Cherokee has the battery under the passenger seat. I'm pretty sure the ground cable doesn't go all the way up to the engine block either.

How do you tie lights in to your floating ground? So if I remember correctly battery ground to ground strip and everything grounded to it. No chassis ground but one to motor, this correct?

The battery is for starting.. all of the sensors
on the car have a common ground so they can talk
to each other.. the alt runs the car and recharges
the battery

We wire are junk with floating grounds.

Keep us posted on your impressions. the Braille 21 lb unit?

What lightweight cable did you go with?

there is someone on this site that sent me a link to the exact battery without the Braille sticker and $140 cheaper.

The lightweight cable I bought is the accel lightning brand but I just bought the negative cable


Just got home and battery and cable are here. My red top weighs 41, my new battery and 20ft of cable weigh 24. I can make a new bat box and shed some weight there also

Might check RJ Racecars/Quartermax on battery cable pricing. Not sure how it compares but where we buy ours at.

http://www.iwsti.com/forums/2-5-liter-li...ka-battery.html

Older post on an STI site, but info still seems valid.

Prices are coming down on the lithium. I just ordered an Antigravity ATX20 Battery for $369 with free shipping. 780 cca, 25 amp hours, under 5 pounds. It's getting mounted on the inside of the framerail, very close to the starter to save the weight and voltage drop of long cables. They said a standard alternator will charge it fine, as long as it doesen't discharge to under 10.5 volts. If it goes under 10.5V, it shuts off and a special charger is needed to wake it up. So I am putting a sensitive digital voltmeter in the car.
I have a 7 year old dyna-batt that is 14 pounds and will start a car, but I don't trust it 100%. So I will build the battery box to fit the anti gravity and the dynabatt, and bring the dyna for a spare.

I'll let you know how it works out.

I'm in the process of building a new car and it will be getting a Lithium battery as well.

We have 1 local racer that has been running one on a sponsorship deal for about 2 years now in a street strip car with great success. It's a 14 volt battery and weighs 14 pounds. Standard alternator, but does take a "special" 10 amp charger that you can get for $35.

Did they mention how the CCA number was achieved? Some of those companies reference a pulse CCA which is done on a 5 second scale as opposed to a 15 second test. The 25 amp hour seems low for the CCA but I am not familiar with the lithium stuff.