The Porsche GT3 RS is a car that uses a lot of exotic materials to try to reduce its weight. Much of the car is made out of lightweight materials such as aluminum, magnesium and carbon fiber. Porsche went to the extremes with the RS to try and make it lighter to the point of it having a stripped out interior, thin glass and even a Porsche crest sticker instead of an emblem on its carbon hood! Porsche also has a lightweight option group called the Weissach package that shaves 39 lbs from the RS for the price of only $31,000! We are going to try to beat that weight loss on Project GT3 RS simply and with a lot less money with the help of our friend at LITE BLOX!
To shave weight off of our car, we opted for the cheapest way to shave a bunch of weight from a bad location in the chassis. The 911 has a heavy battery located high in the front compartment on the firewall. It is mounted about as high on the firewall as possible, probably for easier maintenance. This is good for that but horrible for its effect on the center of gravity. We opted to replace the stock battery with a LITE BLOX LB26XX Lithium Iron Phosphate battery. This is an advanced ultralight battery that is available in the European market and currently undergoing certification for sales in the USA now. It will be available here next year.
Lithium Iron Phosphate battery chemistry has a very high capacity and a long life cycle at lower voltages which makes it ideal for standard automotive applications. The use of phosphates instead of more common cobalt chemistry is easier on the environment in both the mining to get the cobalt and this disposal of it in the used battery.
The LITE BLOX battery is extremely lightweight. LITE BLOX claims a weight of 5.7 lbs for the LB26XX but we weighed it at 6 lbs. At this weight big deal! Porsche has an optional Lithium battery for the RS but it weighs more at 13 lbs. It also costs a whopping $4150 at a discount.
For its light weight, the LITE BLOX battery is amazingly powerful being able to deliver 840 cranking amps for more than 10 seconds of load and an initial 1040 amps to get the cranking started! There is more than just light and pretty behind the LITE BLOX’s carbon fiber case. Of course, carbon is used for its strength and light weight but the outer case is mechanically, thermally and electrically isolated from the inner battery by a layer of molded-in foam that protects the battery and its electronics from impact, heat, and vibration.
Finally, the LITE BLOX battery has sophisticated smart electronic controls to protect the battery from cell imbalance, overcharging, improper charging, and reversed polarity. In addition to those features, the battery has data monitoring and logging of its cells charge state and temperature. LITE BLOX’s battery also has an automatic and remote shutoff with anti-theft provisions built into the electronics to protect the battery from drain in extended storage (up to 300 days!). The batteries controls are accessed via Bluetooth from your cell phone, it’s all pretty amazing!
Since the LITE BLOX battery has a significant weight saving, this could affect the cars corner weights quite a bit. In a prior article, we had shown how much a battery can affect a cars weight distribution and it is significant. In our experience, most decent drivers can feel a 1% change in weight distribution on the track and 1% can make a pretty big change in the cars overall balance. To see how much the LITE BLOX battery would change our car, we corner weighed it first before starting.
Our car ended up being a lot heavier than the 3130lbs that Porsche claims, weighing in at 3248. That is after our car had already lost 15 lbs from the Dundon Motorsports exhaust system we had previously installed. That is a 133 lbs difference! We think some of this discrepancy is due to our optional extended range 23-gallon gas tank that is around 2/3 full. So perhaps some of it is fuel load, some is a heavier fuel tank itself, floor mats and perhaps our factory optional airlift system is contributing to the weight. Our weight distribution is close to 39/61 in our tail heavy rear engined 911 even with our Dundon exhaust taking the weight out of the far rear of the car.