Ok now ready to start modding the engine of Vectra. All I know is its got Ecotec on cover and its the 2.0l. Question is where do I start? Fitted sebring exhaust already and lowered suspension but what about engine mods? Not sure if to go for induction kit as i had loads of problems with K&N 57i and took it back off. Any help or advice as to what to do would be great. Thanks.