I just want to make ignition coil on my own. can you please help to done primary and secondary winding for same..? 40KV output required from 12v input supply.
You need to know not only the turns ratio, you also should know the wire diameter for primary and secondary winding. The core is important and a careful designed isolation. Using only the isolation of the wire would result in a ignition coil destroyed in a very short time by arcs inside the coil. Read here and look at the pictures: https://en.wikipedia.org/wiki/Ignition_coil