What else to look for???

Ok, I've got my friend's '99 SS (Patriot Stg II LS6 heads/Torquer V.2 cam/supporting bolt-ons) dialed in pretty good on AFR (12.3@peak_tq~12.8@peak_hp) and timing (25*@peak_tq~29*@peak_hp). Only have a little burst knock issue to work out. However, it doesn't seem to be making the power it should be...or at least running the times it should be. At the track, he only trapped a best of 110mph with a best ET of 12.34. This was on DR's with 1.7 60' times at roughly 900' above sea level. The air was in the 60's~70's and virtually perfect. What gives? I've been through almost every table in this tune and can't find what's holding him back. The log shows the timing at the #1 cylinder hitting the commanded timing. So, I'm not losing it to the modifiers (like ASPARK, IAT modifiers, etc.).

The only thing I can think of is it's got to be mechanically related. The car is still running the stock 3.23's with a 3500 TCI converter and probably weighs in at 3700lbs with the driver. It leaves the line like a bat outta hell (7.8's in the 1/8th), but seems to fall on it's face the 2nd half of the track. It does spend a bit of time in 2nd. I don't think he hits 3rd until just before the 1000' mark. Any ideas would be highly appreciated!!!