just had vales removed etc then had head skimmed to make sure it wasnt warped then had new valves and valve stem seals fitted. Dont remeber anything about having them re cut and lapped. Done around 10,000 miles since all this work was done. hope it nothing serious otherwise car will be going. Im pretty sure its the exhaust as i read up that if you dont have enough backpressure in the exhaust you will lose a lot of torque so going to get a jetex system fitted.