(just picked up a 96 z28, k&n air filter setup and borla exhaust)and was wondering on some basic tune up things i could do to get better gas mileage more power. ive replaced the plugs and wires with after market custom fit mallory 8mm wires sucks you have to make em. changed oil, fuel filter am going to do the tranny fluid and filterand differential.the car ispretty decent. although i am getting a weird howling noise from the front end and it gets louder when i slowly turn the wheel to the left i think it is a wheel bearing. before i changed the plugs and wires i was getting a multiple misfire code with the obd2 code reader. i didnt clear it with that but i disconnected the battery. i still have that code along with 3 others mass or volume air flow (mass air flow sensor?) code=p0100 nad catalyst system below bank 2 code=p0430, evaporative emissions system incorrect purge flow code=p0441. i am going to try and go back to chacker and get them cleared if anyone has any info or other things i should do to this 144k beast it would be appreciated