Wait, if you're going to stick with K03s, you don't need to (and shouldn't) change anything out in regards to fueling (MAF housing, injectors, etc.).

The only hardware that will return gains with K03s are downpipes (or piggies), cat-back, intercoolers, and water/meth injection. WMI kits are only a few hundred bucks... and can give you race-gas level performance on pump gas... which would only be marginally slower (high-4 FATS) than an APR stage 3 car on 91 octane

 

woops! Im mean I'll be upgrading everything else until my K03s go, then I will go with the min. k04s or better.