Re: Turbo related upgrades (94 S4)

[JShadzi@aol.com]

	<All those changes quoted _will_ change boost, by increasing flow (in 
and
out) of the compressor.>
	Well, yes, but assuming that the manifold is that restrictive to 
actually seriously limit boost.  A serious hog job may get you a psi or two, 
but then your low rpm torque may suffer there because you have reduced gas 
velocities.  Working with the wastegate, ECU (more fuel), and increasing 
turbo flow (RS2) will net real gains in boost.  Check out the FAQ at 
http://www.audi-s-cars.com.  There are some good threads there on this very 
topic.

<Curious, have you flow tested the manifold in question?>
	No, but if you notice the S4 manifold has large diameter runners and 
are only about 4 inches long.  Compare this to the 10v turbo that has much 
longer and narrower runners.  I can almost guarantee that the intake manifold 
is not your weak point in flow.  Those 4 valve heads also flow like banchees. 
 My feeling is that gains are on the exhaust side, such as manifold, turbo, 
and wastegate.  Your friend may have a lot of experience with normally 
aspirated BMWs, but the turbo game, increasing flow is usually the last, 
least HP increasing modification...
Javad Shadzi
86 coupe GT