K&N (just filter), aluminum fw w/Centerforce Dual Friction (crappy combo and actually hurt me a lot), aluminum driveshaft, solid rear axle (as opposed to the stock IRS) with 4.30 gear, TKO (as opposed to TR3650 tranny--stock was more efficient but weak and the TKO robbed a lot of power; it actually made the parasitic loss saved by removing the IRS moot), and 24 inch slicks (275's on 9 inch wheels up front, hehe).
In cooler and dryer conditions, the car probably would have performed much better, but it was in the 90s and 90% humidity when I was running these times. I couldn't get better than high 12.80s and it was running consistent 12.90s/13.00s at about 105. Then I drove down to Miami (from Jacksonville) to get Jerry at SCT to give me a tune (at that point a flash, but I put the same program on a chip later). The dyno results were ok. I went up about 5 rwhp max and I can't remember torque. But what he did was COMPLETELY change the curves.
So I took it to the track and ran a 12.6something right off the bat. The biggest deal was that my mph went up to 110. After that we got it running consistent 12.50s and even a few 12.40s with a best of 12.42 @ 109.55. And this was full weight with larger than stock wheels/tires up front with my large rear end in the seat. The best part was that I could go to my local SCT dealer to reburn the chip with slight changes to improve things here and there. Now, that part is dependent upon the dealer, but I understand most of them will do that. My dealer actually brought a laptop to test and tune and would tune on the spot, but I think THAT kind of service is rare no matter what.
Superchips Custom Tuning:
http://www.sctflash.com/main.php
They are based in Orlando but have dealers all over the country. And they stand by their product. If you get the full package (whatever it's called) you get the burner and everything setup for your car right out of the box. Of course, you can get the tuner, too, but I've always felt they were unsafe as if you have a power failure during the transfer, your PCM will not function and would need to be reflashed by a dealership. That's how it is with Ford EEC-V PCMs anyway.
I loved using SCT and, when I have the money again, I will be using them again for my GTO.