well i decided to replace my them with 750's. Will it have to be tuned before I drive it? Figured id throw them in and then drive it, to get tuned. The car has a hard time starting when cold. this car was originally set up to handle over 800hp and just dont think I need the 1000's. will the 750's give me problems as well? the car has a single turbo thats running around 450whp with a fully built motor and Id like a bit more power, maybe meth and i really only want to change the injectors once..what do u guys reccomend.