My battery on my 2006 Audi S4 (B7) was on it’s way out, so I decided to do some research and try to find a good aftermarket battery to replace the OEM one in my car. My primary goal was to find something affordable and something that is lighter than stock – after much research, I settled on the Optima 34R Red Top as my battery of choice, both due to its affordable price (approx $160 shipped on Amazon) and the fact that it’s 20 lbs lighter than the OEM battery, weighing in at 37.9 pounds versus the OEM battery at approximately 59 lbs. After finding numerous reviews of others running the Optima Red Top without problems, as well as knowing of Optima’s good reputation within the industry, I went ahead with this battery and am quite pleased. This battery will also work on all 2002-2008 Audi A4, S4 or RS4s, known as the B6/B7 platform by Audi enthusiasts.
Check out this battery on Amazon here – ignore the warning that it doesn’t fit your 2006-2008 Audi, it definitely does. Best of it, it ships for free 2-day shipping with Amazon Prime:
My car starts up quicker with a noticeable improvement in cold-cranking power, and although you can’t feel a weight savings of 20 lbs on the “butt dyno” I know that every little bit of weight I can save off this otherwise heavy car is going to help. Between my battery (20 lbs), my carbon fiber hood (50 lbs), lightweight wheels (10-15 lbs) and a big brake kit (10-15 lbs), I figure I’ve saved about 100lbs or more off the front end of the car…It’s also really nice to have a fresh battery, as my car was starting to have annoying problems such as losing the time & date off the dash each time I would leave the battery on without the car running, such as when I was working on the car or detailing/cleaning it with the radio on.
Red Top vs Yellow Top:
If you’re in to high-end electronics, I would recommend the Optima Yellow Top 34 rather than the Red Top, as the Yellow Top is more suited for the deep cycle power you’ll need to power amplifiers and electronics – the Red Top is best suited for cold cranking power as a starting battery. You’ll also want a size 34, but unfortunately Optima doesn’t make this battery with reverse terminals, so you’ll need to install it flipped around to have the positive terminal connect with the positive wire and vice versa. This battery is a little more expensive, but not bad – you can also find it on Amazon.
Installation was fairly simple – I had a nearby shop called Parts Score install it for me while I was having my oil changed and it only took about 10-15 minutes. You could also follow this guide if you try to do it yourself. Afterwords you may need to reprogram your key fob (simply turn between off and accessory on 7 times, you don’t need to start the car just to the first “on” position), and also reprogram your memory seats and radio settings, but that’s it. The Optima Red Top fits just fine in the OEM compartment and no modifications to the mounting brackets are needed – it’s pretty much plug and play! With the battery cover back on, you can’t even tell there is an aftermarket battery installed, as shown above…
I have seen more advanced weight saving batteries and even heard of folks relocating the battery to the rear, but I avoided these for a few reasons. The super lightweight batteries like Braile, although they weigh only like 20 lbs, are much more expensive, ranging from $300-1,500 per battery, and at some point the weight savings just isn’t worth the price. A rear battery relocation also seemed like more work than it was worth, especially when you factor in the weight of adding 0 gauge wiring the length of the car – I also want to keep an OEM look and functionality to everything, so that option didn’t seem worth it to me. The Optima Red Top seemed like a good compromise of OEM performance and quality at a lighter weight and simliar if not cheaper price – a win-win in my book.
Questions or Comments?
Anyone else running an Optima Red Top on their B6 or B7 Audi A4, S4 or RS4? I’d love to hear your thoughts…