Pacembellum

Will putting in a 5lb shorai battery and dropping 30-35lbs off the back passenger side of the C7 z06 cause any balance issues if an equal amount up front isnt removed?

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Hi Volts Z06

If anything it probably will make your cross weight better. GM didn’t design the car knowing how much you weigh (although they probably use 180 lbs as driver weight).

If you really want to dial the car in, have it corner balanced after you change the battery but I wouldn’t fixate too much on it. Just think about how the weight of the car changes as fuel load decreases. 10 gallons of gas is 60 lbs and dual tanks don’t empty equally.

Pacembellum

Well im about 220 with a helmet on if i skip breakfast 😅

GSpeed

Just keep an eye on the electronics. Sometimes, on some platforms, we experience weird issues, as the Battery is unable to support large electrical inrush such as an ABS event.

We have one customer who is using one in a C7Z, but we do not have enough track time yet to know if it will cause issues.

el es tu

Been running them for years - main notes to keep in mind:

I recommend getting the 540 CCA one LFX36L3-BS12

keep the battery on a shorai charger - normal ones can mess it up - if you go to a service center or dealership do not trust them to use a correct charger - they will likely not

let it warm up before starting the car if the temps drop to freezing

dont leave the lights on or a radio (or auxiliary pump running) if the car is not started

Pacembellum

Would running two of them be possible? Also is there a plug in battery charger for the rear that can maintain settings while you change the battery, im familiar with doing that on other cars. Like one of those small lithium jump starters for the rrar hatch12v plug.

el es tu

The charger plugs straight into the battery and has a computer that checks each cell and adjusts the charging accordingly, so Im not sure if using two is a good idea if you go that route.

The battery tender brand of chargers supposedly does not have a desulfation mode so thay can be used with the shorais however Id go with the larger one - the small battery tender brand unit did not work so well on mine. If you used the battery tender brand one you could hook it up to one with a remote cable and it should maintain the two if you wanted to run multiples...

JHrinsin

When looking for a lightweight battery in the past with other "weekend toys" and track cars, I would typically select an AGM battery that was designed for a Harley Davidson Glide or "dresser" model, while a lot of other guys would run the so-called Miata AGM battery from WestCo #12V31M. Now I have never stepped up to the newer Lithium units (they were stupid expensive just a couple years ago) so no opinion/experience with them. The weight saving is fairly spectacular though, but I have also never had a track car with the kind of electrical loading that you might see in a C5 as noted above (if you are still using the ABS), although one of my Fords may have been close and I killed a couple Odyssey PC680 in that car.

The Shorai LFX36L3-BS12 for $330 seems like a pretty good deal - not too much more than the Braile #B3121 that I had in the last car, plus its 16 lbs lighter! Not sure what the difference is between the L3 and A3 models, maybe terminals?

69427

I wouldn't worry about balance issues. The weight reduction is only in the 1% (of vehicle weight) range.

I'll take weight reduction wherever I can find it. It makes life easier on the engine, brakes, and tires.

I agree with some of the previous posters that electrical load/drain issues are a bigger issue to worry about with a small battery.

6SPEEDZ

It will absolutely affect weight balance. It is the the worst place to target weight reduction. It will effectively move weight forward or more specifically to the left front tire. On most tracks that is the tire you use the most. Take a look at a Porsche 911 which has about 40/60 weight distribution. When the 911 gets into the braking zone it dynamically has a 50/50 weight distribution loading the tires evenly. Now look at it weights when you are in a right hand turn where do you want the weight? Certainly not on the left front asking the tire to do more. You want it on the right rear allowing you to get to full throttle sooner. The only place it will help is just raw straight line acceleration. You already handicapped yourself balance wise with a C7 Z06 don't make it worse. Best weight mod would be get a Grand Sport or a full on track C5/C6.

Pacembellum

Chevy didnt put the right engine in the z06 you are right but getting a grand sport was out of the question. No wayyyy was i going to get a sub 500hp vette.

Pacembellum

How about relocate the supercharger coolant tank to the battery location and run a lighter battery. That takes 8-10lbs off the front and puts it where the large battery went.

Hi Volts Z06

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Pacembellum

In your email notice it has a link

Supercharged111

Judging by the design of the C5 seat, I'm willing to be Pacembellum is the low end of what GM targeted the car to.

69427

1) Yes, in theory it will affect the balance, but in practice it will be invisible to 99% of non-professional drivers.

2) Not necessarily. The battery placement/weight is outside the wheelbase. This moment arm increase, while making the F/R weight numbers look artificially attractive, causes sluggish transient handling and inherently promotes oversteer. (I do agree that the rearward battery location is helpful to the straightline crowd.)

3) Yes, but it doesn't change the mass over the LF tire (or the front axle). And it's the mass that has to be coaxed around a corner, not the sum of the weights on the front tires.

4) If you have a 50/50 weight distribution on a 911 during braking, you're not loading the tires evenly, as most every 911 has smaller tires in the front compared to the rear.

5) I disagree. More (normal) force on the tire results in more traction, and more cornering ability. With a heavy battery way out back you end up with a teeter-totter effect. As any third grader knows, if you put weight on one end of a teeter-totter, you remove weight from the other side, making it seem lighter. But, you have not changed the mass! Reducing the extreme rearward weight has multiple advantages. The rear tires do not have to haul as much mass around during cornering, the vehicle is faster to accelerate due to less mass, and the vehicle brakes faster due to less mass. Also, due to the reduced teeter-totter action (forward/rearward of the rear axle), there is a bigger percentage of the actual front end mass pushing down on the front tires for increased traction.

Unless you're stuck in the snow, increased weight is rarely a desired commodity.