Originally Posted by luiscarlos

Cool mod,it is true that in 911 cars it is good to have more weight in the front?

Originally Posted by heavychevy

I think you'll find that most in street porches will get their fastest laps on a full tank of fuel because more weight is in front. And most cup racers add ballast in the front and passenger seat area for balance. However in the grand scheme of things there is more weight to be lost in the back of the car wiwith exhaust, seats, wings etc so it balances out. Plus the battery is pretty high as well so lightening it up some won't hurt and losing 35-40 lbs in conjunction with other weight loss is overall beneficial.

Originally Posted by besiktas

I got a few questions ;

how is the durability? Any potential problems for a daily drive car? cost? And how is the durability vs OEM battery, if we don't use the car for 2 days, do we have to recharge the battery?

Thanks,

Originally Posted by mikymu

The hardest part of the whole switch is making the battery bracket. You don't need to make something fancy like what I did but this give you a general idea on how to secure the smaller Li-ion battery.

I got an aluminum sheet from ACE hardware for the bracket since they are light and easy to work with.



I measure out the length and width of the battery and the distance between two bolts on the body panel (this is where you secure the battery) facing the battery compartment and bend the sheet with the help of a vice. Wood block was used to sharpen the bend (beat the crap out of metal sheet lol)



Test fit looks pretty good



I also made a center brace to prevent the battery from moving up and down. I drilled 4 holes on the center brace then secure it with aluminum rivets. Ignore the extra holes ... they are for cooling lol.

Flat side of the rivet facing the battery. I used couple self adhesive plastic spacer on the center brace to help it fit perfectly





Here is a look of the finished brace

I cut out a none slip plastic mat from Lowe's for the bottom and back side of the battery for extra cushion



You will have to get two longer bolts (about the twice the length of the OEM bolts) from a hardware store to secure the bracket. You may also need to bend the aluminum bracket ever so slightly to make it fit right. Here is what is looks like once installed





Now you have lost 39 lbs total with this mod. This is about 6 to 7 gallon of fuel in weight so the front of the car will be slightly higher. I measured about 1/4" or 6 mm higher each corner on my car. To compensate for this change, I lower each side of the car by turning the suspension height adjustment by two 360 degree turns.



Finish product with everything installed. Connect the remote control wire and push the little button next the the red positive terminal and you are in business!





The car felt great yesterday at Laguna Seca with 39 lbs lighter in the front. The car tun in better. Battery works fantastic too! I intentionally left the interior lights on with both doors open and front hood and rear engine lid up to see how long it take to drain the battery. It took more than 4 hours for the battery to trigger the low voltage shut off. All I had to do is push the remote bottom and we got juice again. Start the engine and the battery was quickly charges. I had no problem at Laguna Seca yesterday and the battery work great with all the electronics without triggering the low voltage shut off. I will give more feedback in 3, 6 and 12 months for long term follow up.

Addendum:

Rad aka NJ-GT gave me a good suggestion that I should put some form of cover between the Li-ion battery and the fuel tank below just in case something happen to the battery that it won't damage the fuel tank case as shown below.



It's a pretty easy mod. You can get a thin aluminum sheet form your local hardware store. Trace out the shape of the heavy OEM battery tray and cut it with a metal sheet cutter.





Test fit the aluminum sheet and I wrap the sharp edge with door edge molding





Finally I cut out a none slip plastic mat from Lowe's for the aluminum sheet and the cover between the Li-ion battery and the fuel tank case is done