S4 NA Flywheel Step Height
 

What is the step height on the S4 N/A flywheel? I have an aftermarket lightweight steel flywheel, and I just pulled off my spec clutch due to it slipping, and it looked like my pressure plate was not putting much pressure on the disc, and there is hardly any wear on the disc, pressure plate, or flywheel. I am going to get the flywheel machined, but I am wondering what the distance should be between the friction surface and the pressure plate mounts in case it is not correct.

That's a good question.
I just had my flywheel skimmed and the shop never asked me for the info, so I assumed they had access to the specs. When I saw your post, I looked in the FSM and couldn't find a step height spec anywhere...which is weird.
Ask your machinist what the spec is and where he got it.

My dad is the machinist, he normally grinds the same amount off of the friction surface as the step height, so that they do not change (measured from an area where the clutch disc does not contact for the friction surface). Since this is a new aftermarket one, it may be incorrect. I have my stock flywheel somewhere, it has been resurfaced at least once, I'll have to dig it out and measure it, if it measures out the same, then its probably correct.

I measured my stock flywheel at 0.635" step height, I had another S4 flywheel, and it was closer to 0.675", but looking closer, it had much more material taken off the clutch face, so I assume its measurements will be less accurate.