well the easiest way is to make a custom engine and edit the ship package to include it ;
the engine _equip.ini has all the engines in it and all you need to know is the max thrust is divided by 600 to give the speed so if you look at the oe_engine package copy and paste it to the bottom (or use FLMM and write a script - the best method) and change the name to one you want and change max thrust to 96000 and you double the speed of your ship
remember to change the goods.ini the use your new engine for the ship of your choice.
all variables are approximations as im a bit pissed right now
dr del
"and that sheep ahs walked bow-legged ever since"