hi not sure if this is 2nd time of putting this matter on the site so i will ask again ,new to forum i have a 2003 ford fiesta with a st150 rear disc conversion it has now failed the mot twice on brake imbalance i have replaced discs and pads as well as brake hoses i have also stripped the rear calipers down cleaned them up fitted new seals as well as making sure there move freely but it still failed from what i saw the near side is around 50% less efficient to the off side is there a brake balance valve or is there something else that could restrict the pressure going to the near side if any one could help it would greatly received