Leather seats will for sure weigh more, I'd be surprised if it was as much as 20 lbs per seat (fronts), could be just 10 lbs more. Just a guess. My L99 is a 1SS/RS. I will try and weigh again this week.
PROJECT HEAVY CHEVY: 2010 Camaro SS/RS |1SS | L99 | CGM
13.15@106 1.95 | 100% Stock
12.06@113 1.70 | Bolt-Ons | Stock 3.27s
Mods: GPI Tune | Bo's PTB | Kooks LTs | Hooker Maxflows | Circle D 3200 | New Era OTR | RCR AirRam Manifold | Powerbond UDP | 3.91s
LSX Record List: http://motorhed.com/xf/threads/lsx-r...the-list.6022/