I've been reading your posts, and honestly, in the heat, for a heavy car like yours I think it is running well (and what I would expect it to run). In cooler air you will probably dip into the 10.90's. That converter change looks like it got you a few tenths (Nice gain), but to run 10.90's in the heat will either take 30+ more HP, or putting that car on a diet to get it down closer to 3200 lbs.

For what its worth, my car runs 10.9's in the heat, but it is about 3200-3250 with driver.

I know you don't want to do this (from previous posts), but dropping the exhaust might get you a tenth or 2...just sayin. Good luck.