How much hp and torque would this mod add to a stock 99 TL? Does anyone know of anyone who has added this to their TL, do you have to program it or does it come pre-programmed? Also how difficult is it to install?

I found it on autocarparts.com.

 

I have it on my TL-S. Unless you are a professional, have it installed by a competent tuner. You will need it tuned on a dyno. Frog Engine Controls has a harness that makes the install easier. Contact "Jaker" on the acura-cl board.