So according to several links on twinturbo.net, and a few on here as well, the TT flywheel should have a 0.008" step up for the clutch contact surface. However machine shops and Exedy (yes I called their tech dept) swear black and blue that 'almost' all Nissan flywheels are flat with no step, including the 300ZX TT. Has anyone ever checked on a brand new factory OEM flywheel if there is in fact a step? What about on an aftermarket lighted flywheel? ie Jun, Fidanza etc? Does anyone know if it's actually referenced anywhere in any official Nissan documentation? From what I've researched most of the time in Aus they are machined flat, and it doesn't seem to cause too much issue. Of course if they are supposed to have a step, and they're machined flat, the clutch plate has to travel that little bit further before it makes contact with the flywheel though.