I think if you up to a 28" slick it may hurt you rather then help you. I ran 26" slicks with 3.73's when I had 479rwhp and it was fine. The only reason I went up to 28" slicks is cause of the hp I am running now and that I want to run 4.30 gears. The initial shock of launching with an auto is never going to be as hard as with a 5spd so you should be ok with a 26" slick. Hope that helps.
I added FOMPK blower cams, 3psi boost and we tuned the combination for the intercooler, forged motor and that is about it. When the car had 479rwhp it wasn't tuned for the intercooler and car was running tad rich and had issues. Now it's more optimized.
Im looking at Hoosier Quicktime Pro 26x9.5x15 to go on a 15x7" rim. ive got a 3.27 gear, will this be to much tire for the gear? should i look for a smaller tire or will i be ok with this, i plan on going to 4.10's probably in the fall when i pull the irs apart. also im only putting down like 220rwhp and car weighs about 4000lbs.