What OEM rear brake kit will be a big upgrade?

 

STi rears
or the other two pots i forget what they come on

 

Subaru makes some JDM 2 pot ones, but you'll need to swap over the whole brake hub.

 

You can add the JDM 2 Pots or Brembo rears rather easily. Most places sell kits with brackets in order to make them fit without replacing the hubs. One thing to look out for is to get rear rotors with spacers inside so that your e-brake is still functional.

 

Is it expensive to replace the hubs. I have a 05wrx and planning to get both the front and rear sti brembos. Where can I get the conversion kit for the rear and how much do they usually cost?

 

you dont have to switch out the entire brake hub for the 2pot subaru calipers, you just need a new backing plate for the new rotor size and has new points for the caliper to mount on, these are sold in almost all 2pot rear kits

 

the sti rears wont fit our wrx's, unless you wanna go to a 6speed transmission with a R180 rear diff, get some STi axles and swap out the entire rear end (and yes thats upwards of $8,000 without labor plus the money to buy the front and rear STi brembo's)... brembo makes big brake kits for the wrx and the kit comes with the gold brembo calipers just like the STi's, gruppe-s sells em