I'm guessing the throttle plates close when you lift, otherwise there wouldn't be enough vacuum for the brake booster, and there would be minimal engine braking.

 

Hmm never seen that before. Cool

 

I know on G35 throttle was limited to around 75% in 1st gear because wide open throttle generated too much exhaust emissions or some such. Uprev Osiris tune removes the restriction and makes it open 100%. G37 comes with VVEL system which is not tunable by uprev or any other tuning software and VVEL has complete control of the throttle position and it's now never at 100%. I doubt it's for any reason other than to control exhaust emissions just like in G35 but you would have to ask Nissan to know for sure.

 

This is not the one I read, but it is much better with the animation..