Originally Posted by Capt Sensible

Another thing to keep in mind, VDW, the FJ is, first and foremost not intended to be a speed racer. Yes you can tweak it to make it faster but at the end of the day, it's still a heavy brick of an SUV.

But more importantly than that, in the most basic sense, HP is for top end driving, torque is for take offs and towing. If you were to go with a full exhaust, you would be drastically decreasing the back pressure on the engine, which in turn will give you a HP boost, but cause your torque to drop. You will have a higher top speed, but it will take you longer to get there, and wont be as pin you to your seat as you're expecting. Plus should you decided to tow anything, you'll probably notice the decline of torque there, and if you go offroad, you might have issues with the torque decline there.

I am but one man, with my own tastes. As are you. Should you want to make your FJ into a performance machine, by all means go for it. But if I were to give you my completely honest opinion, you'd be wasting your time and money.