actual weight - genuine = 29.9 lbs
NISMO = 21.6 lbs
inertial weight - genuine - 3.94 lbs
NISMO - 2.86 lbs
the lighter the flywheel, the quicker the engine revs, both up and down. However, it also means you need more revs when accelerating from a dead stop. The lighter units, by their nature, are noisier than heavier units, as mass acts as a damper of the noises.
Nice one Adam... Just goes to prove you cant read everything you read on there! Esp when lots of it need updating!!