what your wanting to do with a j77, is what a slam overdrive was designed for. darthboba, I talked about them above. They were a type of afterburner designed for the starwing assault missle boat(see seti's list for more detail), that gave accelerated speed up to 3 times the ships normal speed. It allowed for quick maneuvering and escapes during a battle, or surprise attacks. it was designed as a way combat the tie defenders that rogue admiral zaarin had most control of during the tiefighter campaign. SLAM is an anacrynym but I can't remember what it stands for.