Looking for an explanation. Clutch issue *Testing edit*

[Dunckel]

I have a stock flywheel, and an Exedy twin plate clutch.
I notice when I start the car, and the idle goes up around 1500, if I let my foot off of the clutch pedal leaving the car in neutral, the RPMs drop to around 1100 and the car rolls forward just a bit. Maybe like an inch or so. This only happens on cold starts. After a few minutes, when the idle drops down to 800, it doesn't do it anymore. The idle goes up to around 850 when the clutch pedal is pressed in, but the car doesn't move.
So the question is: Why does the car move when it is in neutral? Is it because of a slight touching between the flywheel and pressure plate?

The car runs great, shifts normal, no strange sounds ever.

Thanks guys.
I hope I learn something new.

 

[IJ.]

Thick gear Oil is making the Input shaft/cluster gear act like a torque converter.

 

[Dunckel]

It's not bad is it? I wouldn't think so, being I've had the same setup for a few years now with no ill effects.

 

[IJ.]

Could try a lighter Oil if it bugs you.
(This is why Reverse sometimes grinds and why selecting a forward gear for a second first stops it as it stalls the geartrain allowing the straight cut reverse to select)

 

[AJ'S 88NA]

Mine will do that slighty on cold starts, like IJ said thicker gear oil and the cold.

 

[Dunckel]

Yippee. I learned something new today. I think I need to go dumb myself down a bit now. I'm gonna go play Halo.