Swapped stock gears to 3.27, added killer chiller kit, got tcu tune and my 60 foot sling with quarter mile times are the worst they have every been. Either TCU is just horrible and/or 3.27 gets on the srt6 just straight suck. I have the wavtrav diff as well and just like everyone states with 3.27 gears have less wheel spin but that only because it puts down less power!. I'm st 5600 feet DA today was best out of the entire season. I ran a 13.87, 13.92, 13.91, and two 13.6s at 13.64 and 13.62. 60 foots varied between 2.145 being the best and 2.48 being the worst. Before 3.27 gears and TCU tune in was running 12.7-12.9s all day not problem with 1.8 average 60 foots. 3.27 gears can blow donkey kind D. I'm going back to stock gears and stock tcu tune and I bet my times will be right back in high 12s. Remember I'm at 5600 feet elevation about a full second difference from sea level. I do not suggest 3.27 gears unless your running nitrous out the whole as top end is pretty nice which seems weird. Only positive is crossing the quarter mile while still in 3rd before shifting. Bah humbug 3.27 gears. Sorry