[WorkinLonghorn]

I'm not an expert but GM put a 12" in my truck and there must have been a sound engineering reason for the expense. The more torque an engine is capable of,the harder the clutch must hold. Also the more weight you must get moving the harder the clutch has to work,and the more heat that is generated.A larger flywheel and clutch will be able to absorb and dissipate this greater heat better than a small clutch.Thus the large clutch will be less likely to get glazed over,the Flywheel will be less likely to warp or experience other heat damage.The friction material will last longer in any event.-cougar