Car: '06 Cosmic Grey EP3 prem CTR
Join Date: 30th June 2015
Thanked 658 Times in 621 Posts
Hi, you'll probably not improve the mpg, not a car to get if you don't like 28-32mpg.
Performance, depends how much quicker you want it. Boosted makes the biggest difference, from a personal perspective I prefer normally asperated and to get maximum n/a gains is no cheaper than boosting. Flashpro is a tuning tool that will get the best from any mods you make, usually breathing mods on the k20. It helps give more mid range grunt, and expands the vtec power band.