From now until May, the S4 is only going from my parking spot to the track (or the shop). I didn’t want to completely remove the back seats but I don’t really need them either. There’s airbag sensors in the seat backings, so you can’t remove them anyway without lighting up the dash. It turns out the pass through / arm rest weighs 16.5 pounds, and the rear foam bench weighs 14.5 pounds. They both can be removed (and replaced) in about 5 minutes. So those are in the garage. Then I took the OE trunk floor and used that to separate the cabin.
More importantly, when the rear bench is out the seats fold flatter and the passenger seat can be reclined and slid back further. This moves the weight where I want it, low and in the center of the car. Technically someone could sit behind the driver for a short trip with a seatbelt where the backrest 1/3 split is, but on a hard bottom.
I estimate my weight with 1/4 tank of gas is 3680 pounds. We’ll find out when I corner balance it. This is based on my previous weighing of the car, minus recent mods. I’ve dumped just under 200 pounds from how Audi delivered the car to me.
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