What exact wheels are they mate? Not sure you'll be able to sort it without swapping the wheels out then, maybe you can use another option and upgrade the pads and disc to something better? I can see you're using yellowstuff, is that with standard discs? Maybe get braided lines and better pads and discs and new fluid ... not sure whats really out there for the JDM calipers I used yellowstuff and they faided very quickly on track. Keeping air at them is key though, I'm trying to figure out how to make some airducts to my fronts at the moment so if you got any tips let me know