A couple notes:
- After doing my LS400 brake swap, my braking was much stronger. I ran before and after tests with my 7th grade neighbor in the passenger seat as an unbiased observer. He was laughing all the way home after testing out the LS400 brakes. He felt like he was in a Hollywood car chase scene since we were stopping so much more swiftly than on the stock system.
- When swapping the rears to Supra Turbo calipers and rotors, the car was much less willing to break traction when flooring the brake pedal. On the LS400 fronts only, the rear end would kind of get a mind of its own when braking very hard. As it stands now, I can come to a complete stop from nearly any speed and do so in a straight line with only chirping the tires.
- Correct me if I am wrong, but the 95-00 LS400 used one piston calipers in the rear, on rotors small enough to fit behind 16" wheels. I am sure the brake bias was altered within the hydraulic system between 94 and 95, but that doesn't prevent anyone from buying a brake proportioning valve and fine tune it to find the sweet spot where traction will not be sacrificed even under hard braking.
- Calipers, being locked in place in the wheel well, only affect sprung weight. The 10-12lb difference in total caliper weight between the TT and LS400 brakes would have the similar effect to having or not having your briefcase sitting in the passenger seat. Nevertheless, any weight savings is a good thing.
In summary, the LS400 front brakes by themselves are definitely stronger than stock, and while brake bias is affected, it can be corrected to maximize braking performance with a rear brake kit or a brake proportioning valve.
Summit Racing makes a bias proportioning valve for all of $35 so that you can tune your bias. Search Summit Racing for "SUM-G3905". Here is an article about installing one:
http://www.chevyhiperformance.com/techarticles/71398_install_brake_proportioning_valve/index.html