The more nitro you add, the higher the converter will stall. As high as you stall now, you'll need to have it tightened up or you're throwing away all your torque and gain will be minimal. They can change the fin angle for adjustment until they need to make a stator change. Then at some point, you'll outgrow it and need a larger diameter converter with more stator and fin area.
You only need gear when you lack torque...so as you add nitro, you might want to move to 3.70's or so. Then maybe 3.55 or thereabouts. At 100% nitro, 2.91 is perfect in a FED with a 'glide.
Have fun!
Spud
