Hello have finally starting looking at tuning my 2003 318ti compact. I was just wondering were the best place to start is and the pro's and con's. I have gatherd a few ideas from reading around.
1) Air Intake - How much diffrence does this make and is it a nececery up grade for tuning performance.
2) Re-Map - Will this be a noticable diffrence for the price and will it improve my fuel.
3) Throttle bodys - what/were to get these from and what do they do i am not a 100%
4) Exhaust system - is there a specific type of system i will need to benifit from
Thanks for any help and advice