[s-cars] Differences between RS2 manifold and stock?

[Charlie Smith]

Earlier, Harold McComas wrote:
> 
> Last weekend I was changing out my valve cover gasket and looking down from 
> the valve cover noticed one of my exhaust studs was shorter on cyl # 2 than 
> the others and was wondering how you can tell the difference between stock 
> and the RS2 manifold. Specifically I am looking for installed pictures. I 
> have already checked  the s-cars.org site. The only pics I have came up with 
> are these two:  http://www.urs4.com/technical/engine/EM%20comparo.jpg and
> http://www.euro-audi-parts.com/rs2manifoldc.jpg

They are very easy to tell apart, when viewed from the side as shown 
in the picture
    http://www.urs4.com/technical/engine/EM%20comparo.jpg

The RS2 manifold has the passages from all 5 cylinders joining in
one place - and the stock manifold has 1 & 5 joining above the
connection of 2, 3, & 4.  This means 1 & 5 have more restriction
to flow than the middle three.  You can see this in the picture above.
The picture is somewhat complicated because there is a turbo sitting
behind the left end of the manifolds.

All you have to do is look at your manifold.

    - Charlie