Racing battery question

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swifter

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What's the positive side of running 2 batteries???? Thanks Steve
 
when located in the trunk of the car it helps with weight transfer and traction. the extra amps it provides is also nice if you don't run an alternator on your car. one would think that the extra weight would hinder the goal of faster E.T.'S. that is true to a certain point. however, many a car has ran faster times by adding weight to the rear of the car. sometimes as much as 200 lbs. better traction means more power to the ground, faster 60 ft times, and overall faster E.T.'S
 
We ran 2 batteries in the back without an alternator. We had isolators on each so we could run off both or just one or the other. It's handy like that if you start going rounds and have no time to charge. All you do is switch over to the fully charged battery on board. At our track they often run semi finals and finals very close together to wrap up the day so everyone can go home and we've been almost stuck without time to charge.
 
So if we run a alternator there is no reason to use two batt's unless weight is a issue???? and if so there are other ways to add ballast???? THanks guy's Steve
 
Just run a single yellow top Optima deep cycle battery. I ran my hotrod all day and never put a charger on it.

The weight theory is true as well. Although, I never understood why everyone installs it on the right rear as that is the side that drops the lowest when launching due to torque twist. I installed mine on the left rear hanging off the end (outside) of the framerail.

I also ran a Mopar 100amp mini alternator due to the electronics I used. MSD7al, throttle stop, delay box, cooling fans, waterpump, headlights/taillights etc. etc..
 
LOL. The reason the right rear drops is that's the side the torque tries to pry off the ground with axle / suspension torque, and since the machine cannot "pick itself up" the next best thing is to pull the body down on the axle. Anyway you look at it, on a non- limited slip axle, the right rear is nearly always the one tire which spins.

Putting more weight on the left side is not gonna fix that.
 
LOL. The reason the right rear drops is that's the side the torque tries to pry off the ground with axle / suspension torque, and since the machine cannot "pick itself up" the next best thing is to pull the body down on the axle. Anyway you look at it, on a non- limited slip axle, the right rear is nearly always the one tire which spins.

Putting more weight on the left side is not gonna fix that.


this is truth. its also the reason that super stock springs were designed in such a way that the right rear of the car is higher than the left rear at rest. the right side in a sense holds up more of the rear "body weight" than the left, thus trying to even out the traction to both tires at launch.
 
LOL. The reason the right rear drops is that's the side the torque tries to pry off the ground with axle / suspension torque, and since the machine cannot "pick itself up" the next best thing is to pull the body down on the axle. Anyway you look at it, on a non- limited slip axle, the right rear is nearly always the one tire which spins.

Putting more weight on the left side is not gonna fix that.

I am clear on what the effects of torque is! I have been racing a long time.

If the op is drag racing why the heck would he have a LS diff in his ride anyway. Spool it at least! The left rear raises off the suspension. You put the weight on the right side its gonna drop more.

Proof in the pic of my 8 second 1/4 hooptie,
 

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this is truth. its also the reason that super stock springs were designed in such a way that the right rear of the car is higher than the left rear at rest. the right side in a sense holds up more of the rear "body weight" than the left, thus trying to even out the traction to both tires at launch.

Exactly!!! Why would you put more weight on the right side?????

I preloaded the hell out of the right rear coilover and it still did it! The only thing that really solved the problem was the CE anti-rollbar.
 
I agree that the left rear rises. whats going on with the axle though? the left side tire is planting harder because of the force from the pinion trying to climb the ring gear. it rotates the housing more to the left tire thus putting more force on it while taking pressure off of the right side tire. thus the reason for the battery being on the right side trying to keep even pressure on both tires.
 
your problem is your comparing a ford with even springs to a mopar with uneven springs. Fords have an even front and rear segment whereas the mop has a shorter front segment.

What this does is cause the rear of the car to lift, unlike your ford that is squating and rolling, very different. Mopars lift causing the tires to plant (every force has an equal and opposite reaction)

So yes for your ford its the norm, on a Mopar it is not, infact it is incorrect.
 
I'm going to have to go with 67dart on this one.

The term equal and opposite reactions is what going on here.

The eng is trying to pull the right front tire off the ground, and the drive shaft, is trying to do just the opposite, and pull the Right rear tire of the ground.
 
I am clear on what the effects of torque is! I have been racing a long time.

If the op is drag racing why the heck would he have a LS diff in his ride anyway. Spool it at least! The left rear raises off the suspension. You put the weight on the right side its gonna drop more.

Proof in the pic of my 8 second 1/4 hooptie,

Sorry my friend you are completely mistaken. You are most unfortunately NOT clear on the "affects of torque." The torque of the driveshaft is attempting to lift the right rear tire off the ground. The torque reaction of the engine in the chassis is what is "planting" the rear quarter, and your photo is proof you are mistaken. In other words the body, from engine torque, is trying to twist up off the suspension.

In the same way that a broken engine mount lifts the left side of the engine, the left side of the chassis is being twisted by engine torque

The fact is, if your car "hooked" really really good, you might have been better off putting the battery back in the left front corner!!
 
Sorry my friend you are completely mistaken. You are most unfortunately NOT clear on the "affects of torque." The torque of the driveshaft is attempting to lift the right rear tire off the ground. The torque reaction of the engine in the chassis is what is "planting" the rear quarter, and your photo is proof you are mistaken. In other words the body, from engine torque, is trying to twist up off the suspension.

In the same way that a broken engine mount lifts the left side of the engine, the left side of the chassis is being twisted by engine torque

The fact is, if your car "hooked" really really good, you might have been better off putting the battery back in the left front corner!!

Battery placement on the left rear worked for me!

BTW, that Ford had ladderbars and coilovers. It could hook on dirt with those big tarz!!! :)
 
double the reserve capacity. longer discharge rates, keeping the voltage more consistant throughout the day of racing. However, if a charging system is used, and the battery state of charge is always maintained to 14.2 to 14.6 volts, both the driver and the battery will be very happy! I like the AGM batteries. I use the Optima Yellow top. But if you go to their web site, they will tell you about the red, blue, and yellow top advantages of operation. Just another opinion....
 
Oh and I install my battery in the dead middle of the trunk, as low as possible. just behind the differential cover of my dana. [made a battery holder which allows the battery to be below the trunk floor] then, I tune the chassis for straight, clean equal lift take-offs! I use a ladder bar rear suspension with double adjustable shocks. I also use the wheelie bars...to sometimes fine tune the lift and reaction of the car to the right by adding 1/4 to 3/8" difference from right wheel to left wheel.
 
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