internal balance engine. flywheel is neutral balanced, so if one flywheel is replaced with another, you need to replace with a neutral balance flywheel. the pressure plate is also neutral balanced. any pressure plate that is neutral balanced can be used with any flywheel that is neutral balanced. mix and match any neutral balanced components with each other and no problems will arise on an internal balanced engine. simple as that. pressure plates are neutral balanced with weights welded to them. flywheels that are neutral balanced have holes drilled to balance.