I have a lightweight battery, it's a nice reduction in weight, my battery weighs about 15lbs, you can get them down to almost 10lbs). The stock battery is in the 50lbs range. I've had a LTW battery for 2 years now, no issues starting my car.
The battery is also set to a side to offset the weight of the muffler and such too.
"Driving is like a narcotic, an addiction that can take over lives. It ruins people, breaks families apart, and even kills. Itís habit that needs to be fueled. Time, money, rationality, sweat, knuckle skin, and anyone who disapproves are of little importance to a driver, and are often overlooked. Hi, Iím Nelson, and Iím a drivaholic."