I read somewhere once that Audi did send some 87.5 4000 CS Quattros over to the States with the NG motor. Can anyone verify this? If so, about how many came, and how can you tell, other than by lifting the hood?

Audi never made the 4000 with the 10valve turbo, although it should have been that way.

There have been rumored to have been some really late 4kq's with the 2.3 NG motor. I have never seen one, nor have I spoken with anyone who has. I would assume they came over (if at all!) in CE level trim. Other than that, I don't know of any way to determine the engine without looking at it...

I think he means "NG" which I think means New Generation (I think). It is a 130 HP (140 something torque) 2.3 ltr, 10 valve, 5 cylinder. It was available in the 1987.5 CGT and in the 80/90. Not sure if it ever came on a 4kQ.

If you lift up the hood and look, what should you be looking for to identify a NG engine?

Well, best I can tell you is it has a crisper "squared" look to the valve cover and the intake manifold but the general configuration is the same as the 2.2 110hp engine.