In the states Jim wolf technology sells a flywheel for the S13 / S14 SR20DET engines that has the bolt pattern for both the 240mm clutch setups as well as the 250mm clutch setups from a Z33. This way you can use a Z33 clutch kit on an S14 engine, wich has a lot more surface area and therefor it can hold a lot more power.
Are there any brands who sell in Europe that offer this feature?